CAR - FACT FILE


How To - Helpful Hints
Brakes
Drive Train
Electrical and Lights
Engine
Exhaust and Emissions
Heating and Air Conditioning
Scheduled Maintenance
Suspension and Steering


Return to the top of the page


HOW TO - HELPFUL HINTS
Buying Car Tires: When, Where, and How
Car Fluid Leaks: What to Do
Check Engine Light: What It Means and What To Do
Do I Really Need New Shock Absorbers?
Fuel System Additives: Do They Really Work?
How to Prepare for Changing Seasons
How To Replace Wiper Blades
How to Save Money on Car Insurance
I Have No Heat; What Could Be Wrong?
My Windshield Washers Don't Work! What Could Be Wrong?
Regular Gas: Is It Okay to Use in Your Car?
Tune Up: What Exactly Is It?
Weak Or No Heat? Is It The Heater Blower?
What Does the Term Misfire Mean?
What Is Engine Knocking?
What Is Engine Pinging?
Why Are My Brakes Making Noise?

Return to the top of the page

BRAKES

System Overview

Anti-Lock Brake System


Repairs and Services

ABS Control Module Replacement
ABS Wheel Speed Sensor Replacement
Bleed Brake System
Brake Calliper Replacement
Brake Drum Remachine/Resurface
Brake Drum Replacement
Brake Flexible Hose Replacement
Brake Fluid Replacement
Brake Master Cylinder Replacement
Brake Pads Replacement
Brake Rotor Re-Machine
Brake Rotor/Disc Replacement
Brake Shoes Replacement
Parking Brake Shoes Replacement
Rear Brake Calliper Replacement
Wheel Bearing Replacement
Wheel Bearing Service

Parts

ABS Control Module
ABS Pump
ABS Wheel Speed Sensor
Brake Booster
Brake Calliper
Brake Calliper Pins
Brake Drum
Brake Flexible Hose
Brake Flexible Hose Sealing Washer
Brake Fluid
Brake Hydraulic System
Brake Master Cylinder
Brake Pad Set
Brake Pad Wear Sensors (Electrical)
Brake Pad Wear Sensors (Metallic)
Brake Pads
Brake Rotor
Brake Rotor Pair
Brake Shoe Set
Front Brake Calliper
Grease
Hub Assembly
Parking Brake Shoes
Rear Brake Calliper
Wheel Bearing
Wheel Bearing Seal
Wheel Cylinder

Return to the top of the page
DRIVETRAIN


System Overview

Drive Train

Repairs and Services

Clutch Assembly, Manual Transmission Replacement
Clutch Cable Replacement
Clutch Fluid Replacement
Clutch Master Cylinder Replacement
Clutch Slave Cylinder Replacement
Differential Drain and Refill
Drive Shaft Repair
Drive Shaft Universal Joint Replacement

Parts

Automatic Transaxle
Automatic Transmission
Clutch
Clutch Assembly
Clutch Cable
Clutch Disc
Clutch Master Cylinder
Clutch Pilot Bearing
Clutch Pressure Plate
Clutch Release Bearing
Clutch Slave Cylinder
Clutch Start Inverter (Hybrid)
Cruise Control
Differential
Differential Clutch Kit
Differential Oil
Drive Shaft
Gear Position Sensor
Gearbox Oil
Hydraulic Clutch Assembly
Manual Transmission
PCM (Power Train Control Module)
Pilot Bearing
Shift Control Solenoid
Shift Fork
Synchronizers
Throttle
Throttle Body
Torque Converter
Transmission
Transmission Cooler
Transmission Pump
Transmission Rear Oil Seal
Universal Joint Pair

Return to the top of the page
ELECTRICAL AND LIGHTS

System Overview

Electrical and Lights

Repairs and Services

Alternator Replacement
Battery Cable End Replacement
Battery Cable Replacement
Battery Replacement
Brake Light Bulb Replacement
Door Window Motor Replacement
Door Window Regulator Replacement
Fog Light/Driving Light Bulb Replacement
License Plate Light Bulb Replacement
Side/Marker Light Bulb Replacement
Starter Replacement
Tail Light Bulb Replacement
Third Brake Light Bulb Replacement
Turn Signal Bulb Replacement

Parts

Alternator
Alternator Belt
Alternator Discharge Light
Alternator Harness Connector
Battery
Battery Cable Ends
Battery Control Module
Battery Positive Connector
Battery Post Protective Pad
Brake Light Bulb
Circuit Breaker
Door or Truck Lock Cylinder
Door Window Motor
Door Window Regulator
Fog/Driving Light Bulb
Fuse
Fuse Box
Fusible Link
Hazard Light Bulb
Headlamp Light Bulb
Ignition Distributor
Ignition Lock Cylinder
Interior Lighting System
License Plate Light Bulb
Light Socket
Negative Battery Cable
Positive Battery Cable
Power Seats
Side Lamp Light Bulb
Starter
Starter Relay
Starter Solenoid
Switches
Tail Light Bulb
Temperature Gauge
Third Brake Light Bulb
Turn Signal Light Bulb
Voltage Regulator


Return to the top of the page
ENGINE
Cooling system

System Overview

Cooling System Engine Primary Ignition System Secondary Ignition System Coolant Expansion Tank Replacement Cooling Fan Motor Replacement Distributor Cap and Rotor Replacement Engine Cooling Fan Assembly Replacement Engine Oil and Filter Change Engine Oil Change Engine Oil Pressure Switch Replacement Fan/Drive Belt Replacement Fuel Filter Replacement Fuel Injector Replacement Fuel Pump Replacement Head Gasket Replacement Ignition Coil Replacement Ignition Switch Electrical Portion Replacement Ignition Switch Lock Cylinder Replacement Ignition Wire Set Replacement Lower Radiator Hose Replacement Mass Airflow Sensor Replacement Oil Pump Replacement PCV Valve Replacement Radiator Replacement Spark Plugs Replacement Thermostat Replacement Timing Belt Replacement Timing Chain Replacement Upper Radiator Hose Replacement Valve Clearance Check and Adjust Valve Cover Gasket Replacement Valve Job Water Pump Replacement
Parts

Acclerator Cable Cam Sprocket Camshaft Camshaft Actuator Camshaft Seal Camshaft Sensor Carburetor Coolant Coolant Expansion Tank Cooling Fan Motor Crankcase Crankshaft
Crankshaft Angle Sensor
Crankshaft Pulley
Crankshaft Seal
Cylinder Head
Drive Belt/Fan Belt
Electronic Throttle Unit
Engine Block
Engine Control Unit
Engine Coolant Temperature Sensor
Engine Cooling Fan
Engine Cylinder
Engine Oil
Engine Oil Pressure Switch
Engine Valve
Flex Plate
Flywheel
Fuel Filter
Fuel Injector
Fuel Injector Seals
Fuel Pump
Glow Plug
Head Gasket
Idle Air Bypass Kit
Idle Speed Control Motor
Ignition Cap and Rotor
Ignition Coil
Ignition Coil Boot
Ignition Lock Assembly
Ignition Lock Electrical Assembly
Ignition Module
Ignition Switch
Ignition Wire Set
Lower Radiator Hose
MAP Sensor
Mass Airflow Sensor
O-Ring
Oil Cooler
Oil Drain Plug Gasket
Oil Filter
Oil Pan
Oil Pan Gasket
Oil Pressure Switch
Oil Pump
Oil Pump Gasket
Oil Seal
Oil Sludge
PCV Hose
PCV Valve
Positive Crankcase Pressure
Radiator
Radiator Cap
Serpentine Belt
Spark Plug
Supercharger
Thermostat
Thermostat Gasket
Timing Belt
Timing Belt Idler
Timing Belt Pulley
Timing Belt Tensioner
Timing Chain
Timing Chain Cassette
Timing Chain Tensioner
Timing Cover
Timing Cover Gasket
Turbo Hose
Turbocharger
Upper Intake Manifold
Upper Radiator Hose
Valve Cover
Valve Cover Gasket Set
Valve Cover Seals
VGT Solenoid
Water Pump
Water Pump Gasket


Return to the top of the page
EXHAUST AND EMISSIONS
System Overview

Evaporative Control (EVAP) System
Exhaust and Emissions
Exhaust Gas Recirculation (EGR) System
Fuel Management System
OBD Code P0171 and P0174
OBD Code P0401
OBD Code P0402
OBD Code P0420
OBD Code P0440
Positive Crankcase Ventilation (PCV) System
Secondary Air System
Spark Control System
Variable Valve Timing System

Repairs and Services

Catalytic Converter Replacement
Exhaust Gas Recirculation Valve Replacement
Exhaust Manifold Replacement
Exhaust Pipe Replacement
Exhaust Tail Pipe Replacement
Front Oxygen Sensor Replacement
Muffler Replacement
Oxygen Sensor Replacement
Rear Oxygen Sensor Replacement

Parts

Air Pump
Air Pump Check Valve
Catalytic Converter
Exhaust Clamps
Exhaust Gas Recirculation Valve
Exhaust Gas Recirculation Valve Gasket
Exhaust Gasket Kit
Exhaust Gaskets
Exhaust Manifold
Exhaust Manifold Gasket
Exhaust Manifold to Down Pipe Gasket
Exhaust Pipe
Exhaust Tail Pipe
Front Oxygen Sensor
Gaskets
Intake Manifold
Intake Manifold Gasket
Muffler
Oxygen Sensor
Rear Oxygen Sensor

Return to the top of the page
HEATING AND AIR CONDITIONING

System Overview

Heating and Air Conditioning

Repairs and Services

Air Conditioning Compressor Replacement
Air Conditioning Condenser Replacement
Air Conditioning Evaporator Replacement
Air Conditioning Recharge
Heater Blower Motor Replacement
Heater Control Valve Replacement
Heater Core Replacement

Parts

Air Conditioning Compressor
Air Conditioning Condenser
Air Conditioning Drive Belt
Air Conditioning Dryer
Air Conditioning Evaporator
Air Conditioning Service Kit R12
Air Conditioning System Flush
Expansion Valve
Heater Blower Motor
Heater Control Valve
Heater Core
Heater Hose
Hose Clamps
Refrigerant (R12/R134a)
Refrigerant Lubricant (R12/R134a)


Return to the top of the page
SCHEDULED MAINTENANCE

System Overview

Scheduled Maintenance

Repairs and Services

Air Filter Replacement
Automatic Transmission Fluid Change
Cabin Air Filter Replacement
Cooling System Coolant Change
Manual Transmission Fluid Replacement
Oil Life Monitor Systems
Throttle Body Service
Tire Rotation
Transfer Case Fluid Replacement
Transmission Fluid and Filter Replacement
Windshield Wiper Entire Blade Replacement
Windshield Wiper Inserts Replacement
5,000 Mile Service
6,000 Mile Service
7,500 Mile Service
10,000 Mile Service
12,000 Mile Service
15,000 Mile Service
18,000 Mile Service
20,000 Mile Service
22,500 Mile Service
24,000 Mile Service
25,000 Mile Service
30,000 Mile Service
35,000 Mile Service
36,000 Mile Service
37,500 Mile Service
40,000 Mile Service
42,000 Mile Service
45,000 Mile Service
48,000 Mile Service
50,000 Mile Service
52,500 Mile Service
54,000 Mile Service
55,000 Mile Service
60,000 Mile Service
65,000 Mile Service
66,000 Mile Service
67,500 Mile Service
70,000 Mile Service
72,000 Mile Service
75,000 Mile Service
78,000 Mile Service
80,000 Mile Service
82,500 Mile Service
84,000 Mile Service
85,000 Mile Service
90,000 Mile Service
95,000 Mile Service
96,000 Mile Service
97,500 Mile Service
100,000 Mile Service
102,000 Mile Service
105,000 Mile Service
108,000 Mile Service
110,000 Mile Service
112,500 Mile Service
114,000 Mile Service
115,000 Mile Service
120,000 Mile Service
125,000 Mile Service
126,000 Mile Service
127,500 Mile Service
130,000 Mile Service
132,000 Mile Service
135,000 Mile Service
138,000 Mile Service
140,000 Mile Service
142,500 Mile Service
144,000 Mile Service
145,000 Mile Service
150,000 Mile Service

Parts

Air Filter
Automatic Transmission Fluid
Cabin Air Filter
Cooling System Flush
Transmission Filter
Transmission Pan Gasket
Wiper Blade Assembly
Wiper Blade Refill

Return to the top of the page
SUSPENSION AND STEERING

System Overview

Power Steering
Suspension and Steering

Repairs and Services

CV Boot Cover Replacement
CV Half Shaft Replacement
CV Joint Replacement
Front Coil Spring Replacement
Front Control Arm Replacement
Front Shock Absorber Replacement
Front Suspension Strut Replacement
Front Sway Bar Replacement
Front Wheel Bearing Replacement
Inner Tie Rod End Replacement
Leaf Spring Replacement
Lower Ball Joint Replacement
Power Steering Add Fluid
Power Steering Hose Replacement
Power Steering Pump Replacement
Rear Coil Spring Replacement
Rear Shock Absorber Replacement
Rear Suspension Strut Replacement
Rear Sway Bar Replacement
Rear Wheel Bearing Replacement
Steering Gearbox Replacement
Steering Rack Boot Replacement
Steering Rack Replacement
Strut Bearing Replacement
Thrust Rod Bushings Replacement
Tie Rod End Replacement
Upper Ball Joint Replacement
Wheel Alignment

Parts

Air Shock Absorber
Ball Joint
CV Half Shaft Assembly
CV Half Shaft Boot Kit
CV Joint Kit
Front Coil Spring
Front Control Arm
Front Shock Absorber
Front Suspension Strut
Front Sway Bar
Front Wheel Bearing
Inner Tie Rod End
Leaf Spring
Power Steering Fluid
Power Steering Hose
Power Steering Pump
Rear Coil Spring
Rear Shock Absorber
Rear Suspension Strut
Rear Sway Bar
Rear Wheel Bearing
Spring Eye Bushings
Steering Gearbox
Steering Rack
Steering Rack Boot
Strut Bearing
Sway Bar Bushing
Sway Bar End Link
Thrust Rod Bushings
Tie Rod End


HOW TO - HELPFUL HINTS

Return to the top of the page
Buying Car Tires: When, Where, and How

Tires are the most important, but least appreciated, car part. Good tires can make a car ride and handle like a dream. Mediocre or worn-out tires can make it feel as though you're constantly on a rocky uneven road. Most importantly, the condition and quality of your tires have a direct effect on your vehicles braking performance, so taking the time to educate yourself about vehicle tires may save you more than just your hard earned cash!

All tires look pretty much the same, so it can be a challenge to choose the right ones. Here are some tips to help you make a confident choice.

Never buy used tires! Enough said!

Where to buy.
Use the internet to check prices and tire reviews. Call around to local tire stores to see if they can match the internet prices.

When to buy.
You probably need to replace your tires more often than you think. When the tread wears down, tires can't grip the road well. To determine tread depth, stick a penny with the queen's head top-down into the shallowest groove between treads. If you can see the top of queen's hair, it's time to replace the tire. In areas with a lot of rain, you should use the same "hair" rule with a ten pence piece instead of a penny.

Regardless of tread depth, replace your tires if they are more than 5 years old. To discover your tire's age, find the alphanumeric code that begins with DOT (it may be on the inside sidewall). The two numbers or letters following DOT are the code of plant where the tire was manufactured. The last four numbers tell you the week and year the tire were made: "DOTB71002" means the tire was manufactured in October 2002 in Michelin's Dothan, Alabama, plant and is ready for the recycler.

Also replace tires that show hairline cracks or have been damaged.

How many to buy. It's best to replace all 4 tires. If that's not possible, exactly match the tires you're keeping, right down to the part number. Put the new tires on the rear axle. Having new tires on the front and worn tires on the rear can cause you to spin out if you hit a patch of deep water. When buying snow tires, get 4 or none.

Do you like your car's handling and ride? If so, buy exactly the same tires that are on your car now. A different tire will almost certainly make the car feel and perform differently. If there's something about your car's handling or ride you don't like, you may be able to fix it with an educated change of rubber. Talk to your tire dealer.

All-season isn't. Don't mistakenly assume that an all-season tire has more wet grip than a summer tire. In reality, all-season tires give up grip on both damp and dry roads to get some increased mobility in the snow. If you live where it rarely or never snows, purchase summer tires.

Big wheels keep on turning. Did you buy a car with large-diameter wheels and ultrahigh-performance tires? If so, the car may have a harsh ride, the tires a short tread life, and the wheels may be susceptible to bending. It's possible that a smaller diameter wheel will fit on your car. Go to a wheel store and ask a technician to try one. With a smaller-diameter wheel, you can buy tires with a taller sidewall. Taller sidewalls should provide a softer, but less precise, ride.

They aren't all the same. Michelin owns the Uniroyal and BFGoodrich brands. Goodyear has Kelly-Springfield and Dunlop. Bridgestone owns Firestone. Even if you buy an off-brand tire, it's possible that a quality company produced it. But possibly not. It's best to stick with the most well-known brands. Or you can check a tire's origin by checking the first two letters or numbers behind DOT on the tire sidewall or Wikipedia.

Price range for fitting / tracking / balancing: £0.00 - £0.00

Return to the top of the page
Car Fluid Leaks: What to Do


If it has metal parts and moves, then fluid is most likely lubricating it. There are lots of moving parts in a car. So there are many kinds of fluids. Fortunately, fluids differ in colour, texture, and smell. Once you know what to look for, finding the source of your leak is much easier.

General Fluid Leak Tips

* A puddle 3 inches or wider under your car is considered a serious leak and requires immediate attention.
* A puddle between 1 and 2 inches wide is referred to as seepage or a drip. Unless its brake fluid, the condition isn’t as serious.
* The morning after your vehicle is serviced, check underneath the car for fresh fluid. If any exists, immediately call the repair facility.

Common Fluids Found Beneath Your Car

* Water from the AC or defroster system is one of the most common fluids you may find. Water is formed when moisture in the air comes in contact with the system and condenses. It usually drips under the centre right or centre left of the vehicle. This is a normal by product, and seeing this under your car is no cause for alarm.

* Engine oil. Commonly light to dark brown or black in colour, engine oil feels slippery and may have a dirty, “burnt rubber” smell. To check the engine oil level in your car, see your owner’s manual to locate the engine oil dipstick. If the oil level is low but still registers on the dipstick, top off the oil at your earliest opportunity. Be sure to mention the leak at your next scheduled service. If the oil level does not register on the dipstick, before driving, add enough engine oil to reach the full level on the dipstick. Do not overfill. Overfilling an engine with oil can cause more harm than there not being enough oil. Contact your service centre as soon as possible.

* Coolant. Engine coolant is usually watery and slippery to the touch. It may be light green, yellow, pink, blue, or even purple. It usually drips near the front of the engine or beneath the radiator. After the engine has cooled down (we hope you’re reading this first!), check the fluid levels in the radiator and coolant reservoir tank. If either is low, top them off with distilled water. Do not use tap water: it contains minerals that can lead to cooling system corrosion. The number 1 cause of serious engine damage is loss of coolant. If your car consistently continues to lose fluid, contact your repair centre immediately.

Less Common Fluids Found Beneath Your Car

* Automatic transmission/power steering fluid. These fluids can be similar and sometimes identical, so have a professional repair facility confirm the leak. Automatic transmission/power steering fluids are usually reddish to reddish brown in colour and feel oily. Leaks are usually found under the transmission or transaxle. These fluids also may leak from a transaxle cooling line near the radiator.

Power steering fluid leaks are found under the front of the engine near the power steering pump or toward the rear of the engine at the steering rack. Check the fluid level. If it doesn’t register on the dipstick, immediately contact your repair centre. If fluid is still on the dipstick, top off the fluid, and monitor how much and how quickly it’s leaking. If there is regular loss, have your vehicle inspected by a professional.

* Manual transmission/differential fluid. Leaks of this thick oil, which has an objectionable “rotten egg” smell, are found under the front and rear differential, manual transmission, or transaxle. It’s difficult to check these fluid levels, so have your vehicle inspected by a professional.

* Brake Fluid. Fortunately, leaks of this fluid aren’t common. Brake fluid looks like white wine when it's new and dark tea when it’s old and dirty. Because brake fluid is based on vegetable oil, it feels oily. If you find leaking brake fluid, check the level in the brake master cylinder reservoir. If the level is low, top it off. Brake fluid eats through paint with zeal, so use caution when topping off. Use only the DOT-grade brake fluid recommended in your owner’s manual. If leaking continues and the fluid level is below the midpoint, have your car towed and inspected for a brake fluid leak. This is a real safety issue.

If your car has a manual transmission, it may use a hydraulic clutch, which also uses brake fluid. However, the clutch and brake reservoirs are almost always separate for safety reasons, even if they use the same filling point. If there is a brake fluid leak and the brake master cylinder is full, then it is most likely a clutch fluid leak. One indicator is that the clutch won’t operate as easily; sometimes it can be impossible to shift gears.

Price range for Leaks: £0.00 - £0.00


Return to the top of the page
Check Engine Light: What It Means and What to Do


The check engine light (CEL) is a warning indicator: it means your car's computer has determined that a component or system in your emission controls is not working properly.

Every vehicle manufactured to be sold in the U.S. has to pass an Environmental Protection Agency (EPA) test procedure called the Federal Test Procedure. This sets the acceptable limits of wear and/or failure for the emission-control system—i.e., what conditions ultimately cause a Check Engine Light to illuminate. These standards are closely regulated. If the emission-control system is faulty and the vehicle is polluting the air, the Check Engine Light illuminates to alert the driver of this condition. (A vehicle in this condition would fail an emissions inspection during MOT testing.)

Don't confuse the Check Engine Light with the maintenance or service light. These lights illuminate when a routine service is due. They are usually triggered by mileage, gallons of fuel consumed, or some other type of vehicle-use measurement.

The 4 Most Common Check Engine Light Scenarios and What to Do
The Check Engine Light turns on and off or flickers.

If the Check Engine Light comes on in the city but goes off on the freeway, then the fault is present during city driving conditions. Pay attention to whether or not the vehicle runs or drives any differently when the Check Engine Light illuminates. If vehicle performance does change, drive the car as little as possible and take it to be checked by a service professional as soon as possible. If there is no change in vehicle performance, you can drive home and to a shop, but have it inspected as soon as possible. In this condition, you run a risk of the vehicle dying or not starting.

The Check Engine Light comes on and stays on.

If the Check Engine Light illuminates constantly during driving with no noticeable driving or performance problems, there is a permanent fault in the emission-control system. When this happens, the computer that controls the emission system usually has a backup program that runs while the fault is present. You should get the vehicle serviced as soon as possible, but in most cases, the vehicle will continue to operate, though you run a risk of it dying or not starting.

The Check Engine Light illuminates stays on and there are performance problems.

This means that a vital component of your emission-control and engine-management system has a serious problem. It usually involves a component or system needed for the vehicle to run at all. In most cases, drive the vehicle as little as possible. In many cases, the vehicle is not safe to drive at all—it could stop or stall out at any moment. It is best to pull over to a safe place and have the vehicle towed to a repair centre with a diagnostic system for a thorough inspection and repair.

The Check Engine Light comes on and blinks in a steady pattern while driving.

Don't confuse this steady pulsing of the Check Engine Light (usually one or more flashes per second) with a flicker (see above). The Check Engine Light may stay on steadily, or it may flash when the vehicle is accelerated. This is very serious. There is a severe failure of the emission-control system that is causing the engine to misfire to the point that the catalytic converter is damaged each time the Check Engine Light flashes. It may mean that the catalytic converter is overheating to the point that it will glow red or, in extreme cases, start a fire on the underside of the vehicle. Immediately pull over to a safe place and have your vehicle towed to a repair centre for repair. Vehicles can be severely damaged and even destroyed by fire if this condition is ignored for too long.

Price range for Engine inspection: £0.00 - £0.00


Return to the top of the page
Do I Really Need New Shock Absorbers?


Worn shock absorbers affect the way a car handles and brakes. Worn shock absorbers affect tire wear and ride quality for the passengers. A vehicle with worn shock absorbers may continue bouncing after driving over bumps or may feel as though it is constantly bobbing when driving on the freeway. Worn shock absorbers can also contribute to front-end “dive” when the brakes are applied.

A shock absorbers primary function is to dampen or resist the coil spring's "springing" action. It smoothes the initial bump (compression) and controls the bouncing "rebound" of the spring. Worn shock absorbers are no longer able to react to changes in tire contact with the road surface during cornering, or when varying surface conditions are encountered (pot holes and speed bumps).

Premature shock absorber wear may be a result of driving habits, either by aggressive driving on rough road surfaces, or in the case of commercial vehicles, if recommended loads are exceeded.

Shock absorbers can be tested by the old fashion "bounce test". Many modern cars use light weight body panels so be careful not to apply excess force to the fenders as you can easily damage the fenders. Bounce the car up and down applying pressure to each corner of the vehicle one at a time. Press down and release to get full suspension travel three times and let go, the vehicle should rise and fall and then settle if the shocks are good. A good shock absorber will resist the constant bouncing of the spring.

The bounce test is not the sole indicator of worn shock absorbers. Visually inspect the shock absorbers for signs of leaking hydraulic oil. The shock absorbers or suspension struts should appear dry and free of oily, dusty residue. Look at the shocks on each side of the vehicle (both sides-front and both sides-rear) for comparison, they should visually appear similar.

Worn shock absorbers on a very heavy car seriously compromise road handling to the point where the car may become dangerous to drive.

Price range for Shock Absorber fitting: £0.00 - £0.00


Return to the top of the page
Fuel System Additives: Do They Really Work?


As required by the EPA, all gasoline sold in the United States must contain a minimum level of deposit-control additive to prevent build up of sediment in your engine and fuel system. However, just because a fuel meets EPA minimums doesn’t mean it prevents deposits from forming.

Check any auto parts store shelf, and you’ll be overwhelmed by the selection of aftermarket fuel system and gasoline additives designed to do everything from cleaning fuel injectors to boosting power and fuel economy to improving your sex appeal. But do they all work as advertised?

Fuel System Cleaners

Although you’re out of luck on the sex appeal front, there are some additives on the market do indeed help keep engines clean. Some can even remove existing deposits left by lower-quality petrol and help restore your car’s original performance. Chemistry plays a large role in an additive’s effectiveness. Some fuel system cleaners contain polybutene amine (PBA) chemistry and can remove deposits from

* Fuel injectors.
* Carburettors.
* Intake valves.
* Ports.

They can also help

* restore lost engine performance.
* help lower engine emissions.

However, that’s where PBA’s benefits stop. In fact, additives with PBA chemistry actually contribute to combustion chamber deposits, which can potentially cause engine knock and increased emissions.

More advanced additives, especially those containing polyether amine (PEA) chemistry, can deliver additional benefits, such as cleaning combustion chambers, reducing engine knocking and pinging, relieving cold-start up issues, and removing harmful sulphur deposits from gas gauge sensors to protect them from malfunctions.

In fact, many car dealerships use PEA chemistry in the fuel injection–cleaning service they offer. So instead of paying £90, head over to your local car parts dealer once every 3,000 miles, buy a fuel system cleaner with PEA, put it in with a full tank of gas, and save £85.

Fuel Economy and Power Boosters

As fuel prices rise, there’s increasing controversy surrounding aftermarket additives as well as chemicals like acetone and whether they actually help improve fuel economy and power.

Many don’t. Ignore additive makers’ claims of all sorts of additive benefits; rely only on years of proven science. If the manufacturer can’t prove measurable gains in a laboratory environment over years of testing, it’s snake oil. Remember: if it sounds too good to be true, it most often is.

Price range for Fuel system Additives: £0.00 - £0.00


Return to the top of the page
How to Prepare for Changing Seasons


The shifts in temperature and moisture that accompany changing seasons can take a toll on your car and on its performance. Have the following services performed at least twice each year.

* Check your antifreeze/coolant level. The most common cause of engine-related breakdowns is cooling system failure. If you top off the coolant yourself, check the label on the coolant bottle to ensure it's the recommended type for your car make and model. Use a 50:50 ratio of antifreeze to water.

* Replace your windshield wiper blades every year. In extremely cold climates, fill the washer reservoir with freeze-resistant wiper fluid (water and standard windshield washer fluid will freeze), and keep an extra gallon in the trunk.

* Check your battery. If it is more than 3 years old, have a service technician test its capacity and the output of your alternator. Make sure the battery terminal ends are corrosion-free.

* Check your tire pressure before you've driven more than 15 minutes. This lets you ensure that tires are inflated to the proper pressure (listed on the sidewall). In colder weather, the air inside the tires will contract, and the pressure will drop.

* Check the tread depth on your tires. Hold a penny between the treads. If you can see the top of the queen's hair, it's time to replace the tire. In areas with a lot of rain, you should use the same "hair" rule with a nickel instead of a penny. In snowy/icy climates, consider changing your regular tires to winter/studded tires for the season.

* Check that your lights, heater, and defrosters are working properly. Before summer, have the AC system checked and recharged if it's not doing a good job cooling incoming air.

* Check all rubber hoses and belts to ensure they are not damaged. Coolant hoses wear from the inside out. Inspect for heavy cracks in or chunk missing from the belts.
* Have your car's brake system checked if you haven't had it inspected in the previous 6 months.

* Assemble a winter emergency kit to keep in the trunk of your vehicle. The kit should include a blanket, extra boots and gloves, an ice scraper, windshield washer fluid, jumper cables, a first-aid kit, flares, a small snow shovel, a flashlight, kitty litter (for traction when stuck in the snow), and bottled water. Bottled water is good to keep in the car regardless of the season; you want to stay properly hydrated if you have to wait for help by the side of the road.

* In very cold climates, consider changing to a "winter weight" motor oil, which works better in lower temperatures (regular oil grades get too viscous at low temperatures). 5w-30 is a typical winter-weight motor oil.

* Keep the gas tank 1/2 filled all winter long. This reduces the likelihood of moisture build up in the fuel lines. Moisture build up increases the likelihood that fuel lines will freeze and fail.

Price range for Seasonal checks: £0.00 - £0.00


Return to the top of the page
How to Replace Wiper Blades


It is not difficult to replace wiper blades on cars but remember incorrect installation of the replacement wiper blades can scratch or even crack the windshield. Please use caution!

With newer vehicles it is often economical to use wiper refills available from the dealer or car parts store. The refills, if available, only replace the worn rubber part of the wiper. If you still have the original wiper blades on the vehicle, it is worthwhile to call around about pricing. They typically slide out of the blade once a locking clip is released.

It is common to see cars that no longer have their original wipers, so refills are not always an option. Below is a typical installation procedure for installing wiper blades on a vehicle. Often your owner’s manual will have good instructions with diagrams illustrating the replacement procedure.

Step 1:
With the ignition keys removed from the ignition switch, lift the wiper arm away from the windshield. It should pivot away from the windshield and come to a position where it will “lock” in a position that will allow you to replace the wiper blade. If your windshield wipers are concealed by the hood, do not force them to move.

Step 2:
Detach the old wiper blade from the wiper arm. There is usually some form of a detent that has to be pressed to allow the blade to be released from the wiper arm.

Step 3:
Detach the old wiper blade from the wiper arm.

Step 4:
Attach the new wiper blade to the wiper arm and ensure the new wiper blades are securely attached to the wiper arms. Also verify the new wiper blade is the same length the old one.

Step 5:
Gently place the wiper arms back on the windshield. Clean the windshield with glass cleaner and operate the windshield wipers with the windshield wet to ensure wiper blade travel on the windshield is correct.

Price range for fitting of new Wiper blades: £0.00 - £0.00


Return to the top of the page
How to Save Money on Car Insurance


In today's tight economic times, most people are looking for ways to rein in their spending and cut down on their bills. One monthly cost in particular that many individuals and families are trying to reduce is car insurance. From downsizing liability to property damage coverage, many drivers are turning to bare bones auto insurance coverage.

However, not having adequate coverage could lead to serious financial problems if you end up in an accident.

Five Ways to Save Money on Your Car Insurance:

1. Increase your excess. If you have a good driving record, trust your ability to remain claim-free, and can afford the higher out-of-pocket costs when you file a claim, then a higher excess can be a great way to save on your monthly premium. Stay out of harm's way on the road and you should save money in the long-run.

2. Consider advance driving school. Defensive driving courses are not just for 17 year olds. Many insurance companies will reduce premiums for drivers who complete an advance driving program. Strap on your driving helmet and hit the books it could help you score a discount on your premiums.

3. Shop, shop, and shop. Take advantage of the competition between insurance companies by going online and conducting a shopping comparison. Get multiple quotes before settling on your new policy to ensure an exceptional deal. The first quote may have a great-looking price, but you may be able to find an even lower one.

4. Get discounts for multiple policies. Most insurance companies offer discounts for clients who have more than one policy with their company. If you have a homeowner's, life insurance, or business policy with a given company, ask your rep for a discount if you give the company your car insurance business.

5. Improve your credit rating. Here's a little secret about how your car
Insurance company sets your rates; it takes your credit scores into consideration. You may find yourself paying higher premiums if your payment history is spotty or you have a bad credit rating. Look to improve your credit score by paying your bills on time and by checking your credit report for inaccuracies.

It's understandable to put paying the mortgage or rent ahead of your car insurance premium but a no frills, bare bones policy could set you up for a financial catastrophe in the long run. Instead, look for creative ways to save on your car insurance, you may be able to save more money than you think.

Price range for Car Insurance: Varies pending on car, location, age and gender.


Return to the top of the page
I Have No Heat; What Could Be Wrong?


The heater functions with the help of the heater controls inside the passenger compartment, and a healthy cooling system. Depending on the symptoms, there are different areas to concentrate your diagnosis.

Completing our Heater and A/C Diagnostic Assistant can help your technician duplicate the complaint and diagnose your heater problems.

Engine temperature gauge is normal but I have no heat!
First, check your engine’s coolant level. If the coolant level is low, air may become trapped in the heater core and coolant flow through the heater core is critical for heat output.

While it is running, heat produced by the engine is absorbed by the engine’s coolant and flows through the heater core. The heater core is a little radiator usually located behind the dashboard in the passenger compartment and is the heat source for your vehicle’s climate control system.

Always exercise extreme caution when checking anything in the engine compartment as many engine components can be hot, and unintentional contact with rotating components may cause injury.

Debris may restrict the heater core, particularly if someone has used excessive amounts of a “stop leak” product to address a coolant loss problem. Locate the heater hoses that carry coolant to the heater core, they will be at the rear of the engine compartment and approximately an inch in diameter. With the engine at normal operating temperature, feel for a noticeable temperature difference. With the temperature controls set to the full hot position and the heater blower off, the two hoses should be the same temperature. If there is a significant temperature difference, this may indicate a plugged or restricted heater core. Flushing the cooling system and disconnecting the hoses that are attached to the heater core to inspect coolant flow through the heater core may be a worthwhile maintenance.

Does your vehicle have a heater control valve installed inline in a heater hose? Only some cars made recently have a heater control valve either operated by a cable attached to the heater controls on the dash or controlled by a vacuum signal. (Vacuum operated heater control valves are more common on cars with climate control heating/air conditioning systems.) If equipped, verify the heater valve is not blocking coolant flow to the heater core (you may need to have the engine running). Have a friend operate the temperature control and verify the valve’s operation.

Engine temperature gauge is higher than normal but I have no heat!
If your temperature gauge is showing higher-than-normal temperatures, there could be a restriction in the cooling system. This can often be caused by a defective thermostat that is stuck in the closed position or other restrictions. Be careful to not overheat the engine and don’t wait to take care of cooling system problems!

The air is cold at the stop light but warms when I start driving again!
A healthy cooling system is critical to heater operation and “fresh” coolant needs to be constantly flowing through the heater core. An inefficient water pump can create symptoms like this. As the impeller in the water pump wears, it becomes less efficient when the engine is idling. A restriction somewhere in the cooling system may also contribute to this symptom. You may also notice the temperature gauge reading higher than normal. Careful diagnosis is needed in this case and be careful not to overheat your engine!

The engine takes forever to warm up, or never warms up!
If your car is slow to develop adequate heat when the engine is started from cold, or the engine takes a long time to “warm up”. Take note of the temperature gauge. The engine should reach operating temperature, approximately the middle of the gauge, after about six to eight minutes of running. If the temperature gauge needle always remains in the bottom third of the gauge it is likely the cooling system thermostat has failed.

My cooling system is fine, what else could it be?
If you are certain the cooling system is functioning normally, it is possible the source of the problem is in the heater controls.

As mentioned earlier, some cars have a heater control valve and many manufacturers have switched to temperature blend doors inside the heater/HVAC housing. Poor heater operation may be due to heater controls that are not functioning correctly. Climate systems usually operate using cables, vacuum or electronic signals and actuators.

Hot/cold temperature blend doors commonly fail on many new vehicles. Depending on the model, it may be the door that fails, the actuator that moves the door, or the signal to the door (whether it’s an electrical signal, cable, or vacuum). With temperature blend doors, coolant is always flowing through the heater core. Air in the heater housing is diverted around the heater core in the heater housing. A defective blend door may not allow the air pass through the heater core and therefore, never warms up.

Price range for fixing Heating problem: £0.00 - £0.00


Return to the top of the page
My Windshield Washers Don't Work! What Could Be Wrong?


First, check that the windshield washer bottle has fluid and that fluid is free from debris or algae growth. If the fluid is contaminated the washer reservoir should be drained and cleaned.

Open the hood and locate the windshield washer reservoir. On some vehicles it may be located under either the front fender or bumper. The owner's manual will often tell you the location of the washer reservoir.

Do you hear the windshield washer pump operate when you operate the windshield washers? It may help to have a friend operate the washer pump while you listen. If the pump is not heard check the fuse panel to see if there is a blown fuse. There may be more than one windshield washer pump if your vehicle has a headlight washer system or rear windshield washer. You may need the owner's manual or an electrical diagram to determine which fuse protects the washer system if it is not clearly marked on the fuse box cover. If no fuses are found to be blown, and the washer pump makes no noise when the switch is activated, one of the components may be defective (the switch, washer pump, relay if equipped, etc).

If the washer pump appears to operate, fill the reservoir and inspect for any leaks, perhaps from a defective reservoir or seals. Then activate the washers and inspect the system for leaks from the hoses that carry washer fluid to the washer nozzles or jets. Many times heat from the engine compartment deteriorates the hoses over time or rodents actually chew through the hoses. If no leaks are found disconnect the washer tube carrying fluid to the washer nozzles, there is usually a convenient junction around the hood hinge. Operate the windshield washers again and see if fluid squirts out of the hose with sufficient volume and pressure, if not, the pump may be weak or the washer fluid is facing a restriction in the lines due to dirt or a kink in the washer hose.

If washer fluid does squirt out of the washer hose you may have a restriction in the washer nozzles themselves. This restriction may be caused by contamination that has entered through the washer reservoir or the washer nozzles may be blocked from car wax that has hardened from the last time you waxed your car! A small needle can be used to clear the washer jet if it is wax or blocked from the top side of the nozzle. You may need to use compressed air to clear stubborn debris that has lodged in the washer nozzles.

Price range for fixing of Windscreen Washer Pump: £0.00 - £0.00


Return to the top of the page
Regular Fuel: Is It Okay to Use in Your Car?


It's happening to most of us. As fuel prices rise, we look for ways to save money on what's beginning to feel like liquid gold. Some options include car sharing, taking public transport, working from home, and cheating at the fuel pump. Sure, your cars owner’s manual says to use premium fuel, but filling an empty tank with premium can cost as much as £9.00 more than a tank full of regular. Do you take the chance on cheaper fuel? Can using regular fuel when your car calls for premium harm the engine? Depending on what type of vehicle you have, yes, it can.

The Differences

When fuel with an Octane Number Requirement (ONR) lower than recommended is used in a vehicle, the pressure and heat produced by the engine ignite the fuel rapidly and unevenly. This is what causes the dreaded pinging or knocking noise most often heard under heavy acceleration or load. Do these noises indicate harm to your engine? If it happens only occasionally, it isn't serious, but frequent knocking can cause

* decreased power.
* Engine deposits.
* overheating of engine components.
* Engine damage.

Newer cars have a sensor that detects knocking. The sensor makes preventive adjustments when you use lower-ONR gasoline. But these adjustments come at the cost of power and acceleration.

In the long run, if you use regular fuel when your owner’s manual calls for premium, harmful engine deposits will accumulate. This can not only increase the likelihood of knocking but also can increase emissions while reducing fuel economy.

In sports cars with turbo- and superchargers, using a lower than recommended ONR fuel is an especially dangerous proposition, particularly if the vehicle is driven hard and sees excessive boost pressure. The potential damage can be catastrophic and expensive.

In Summary

Although it's possible to use lower grade fuel than recommended, the money you save now will disappear the moment your car has to go into the shop for engine repair or replacement. If you occasionally need to use lower grade fuel because premium isn't available, don't fret, but don't make it a habit. If you want to keep your car running strong and well for many years to come, always follow directions in your owner’s manual and fill up with the recommended grade of fuel.


Return to the top of the page
Tune Up: What Exactly Is It?


The phrase "My car needs a Tune Up" is probably the most spoken phrase by car owners on a day by day basis in the Automotive Service and Repair Industry other than "Oil and Filter Change". When a Service Writer or Technician asks the driver why the vehicle needs a "Tune Up", the customer will usually say that the vehicle does not run properly in some way.

It could be idling rough, it could be hard to start, it could lack power, it could be getting poor mileage or have many other possible symptoms. Many people believe that a "Tune Up" will solve all or most of these problems, but modern cars do not require "Tune Ups" and poor performance almost always means the car needs a repair.

The phrase "Tune Up" is from a time when cars were not computer controlled and a car Mechanic could actually adjust the Timing, Idle Speed, Fuel Mixture and other things to "Tune Up" the operation of the Engine, very much the way a Piano Tuner will "Tune Up" a Piano to bring it back into proper pitch and operation by adjusting the tension on the strings, adjusting the action and reshaping the hammers.

Maintenance: The Modern Day Tune Up

Presently the term "Tune Up" actually refers to replacing and servicing the wear items in the Ignition System and Fuel System.

* The Air Filter and Fuel Filter will become less efficient and need replacing.

* The Spark Plug electrodes will wear down and need replacing.

* There will need to be some cleaning or decarbonising of the Throttle Body and Fuel System from the Oil Vapours produced by the Positive Crankcase Ventilation (PCV) System.

There are no adjustments needed (or possible) for the most part, because the Engine Computer Controls all the functions of the Ignition and Fuel System. The "Tune Up" is often part of a large 30,000 / 60,000 / 90,000 mile service that includes inspections, fluid and filter changes, and these services are part of the manufacturer's recommended scheduled maintenance detailed in the vehicles owner's manual.

The present day vehicle should not exhibit any performance problems by the time a "Tune Up" is due. If there are any performance problems, usually a Check Engine light will illuminate, indicating that the vehicle needs some attention because it is not running properly and is now polluting the Air.

Price range for Servicing: Varies – Interim: £0.00 - £0.00
###### Full: £0.00 - £0.00
###### Major: £0.00 - £0.00


Return to the top of the page
Weak or No Heat? Is It The Heater Blower?


The heating and air conditioning system in your car uses an electric blower motor (fan) to circulate air in the interior of the car. Depending on the setting, the heating and air conditioning system can provide hot or cold air and/or defrost the windshield, as well as provide passengers comfort.

Heat is delivered when the blower motor blows air through the heater core and then out of the vents. The air being blown through the heater core picks up heat and the setting at which the blower control is set determines how much air is then blown from the vents.

The blower motor is usually located under the glove box area of the dashboard inside the heater housing that also contains the heater core, and flaps that divert air to the windshield, foot well area, panel vents or defroster vents.

Circuit Protection: Fuses

The blower motor is protected by a fuse if you find the blower motor is inoperative. You may need your owner’s manual or workshop manual if the fuses are not clearly labelled on the fuse box cover. If you replace a fuse, and it blows again something is causing too much current draw through the circuit. This can indicate a failing blower motor or other electrical fault.

Blower Motor Control: Blower Motor Resistor faults

The driver also controls the speed at which they want the blower motor to operate. The blower motor speed is usually controlled by a series of resistors in a blower speed module (blower motor resistor) or by a blower speed controller. If the blower motor only operates on high speed the blower motor resistor has probably failed. Again, thoroughly inspect your fuses before replacing any components. A wiring diagram will be needed to properly test the heater blower motor controls.

Air Flow: The Blower Motor

The blower motor itself is easily accessible on many vehicles being located in the passenger foot well area and can be replaced with a minimal amount of disassembly; however some manufacturers require major dash disassembly to gain access to the blower motor.

Get a free estimate for the Heater Motor replacement on your vehicle!

Clean Air: Cabin Air Filter (Dust and Pollen Filter)

If your vehicle is equipped with a cabin air filter, poor blower motor operation may be due to a partially clogged cabin air filter.

Clean Those Leaves!

The air intake for most heating and ventilation systems is the plenum tray, at the base of the front windshield. Cleaning leaves and debris from the panel beneath the windshield may also dramatically increase the efficiency of your heater blower motor. Keeping this area clean also keeps debris from falling into your heater housing. Organic plant matter inside the heater box can lead to mould and mildew build up, which is usually the cause for the "funny [read-rotten] smell" when you turn on your heater!

Price range for Fixing & Labour of Blower: £0.00 - £0.00


Return to the top of the page
What Does the Term Misfire Mean?


Generally, the term misfire refers to an incomplete combustion process inside the cylinder. When this becomes severe enough, the driver will feel a jerking action from the engine and/or power train. Often the owner will bring the vehicle into a shop complaining that "the timing is off." This is partially correct because a misfire does involve a mistimed combustion event. However, the base ignition timing being out of adjustment is only one reason for a misfire to occur—and not the most likely.

Here are some of the most common misfire scenarios.

Ignition Misfire:

An ignition misfire is one of the most common reasons for an engine to misfire. As the spark plugs, ignition cables, distributor cap and rotor, and ignition coil wear over time; their ability to transfer the needed spark to ignite the air/fuel mixture inside the combustion chambers becomes compromised. In the early stages, the spark will only be weaker and the actual misfire will be subtle. As the ignition components continue to wear, the misfire will intensify and the combustion process can be interrupted completely. This will cause a severe jerk or shock in the operation of the engine (the engine can even backfire through the air intake system).
Any ignition misfire will cause raw, poisonous hydrocarbons to be released into the atmosphere. This is why all 1996 and later fuel powered vehicles having a dedicated "misfire monitoring system" built into their emission control systems. Raw hydrocarbons can also destroy a catalytic converter, so 1996 and later vehicles will flash the Check Engine Light to alert the driver of a misfire condition.

Lean Misfire:

The lean misfire is another common reason for an engine "miss" this is due to an imbalanced air/fuel ratio (too much air). Since an engine needs a richer (more fuel) mixture for a smooth idle, this problem is more noticeable when the vehicle is idling. The lean misfire may decrease or disappear as the engine speed increases because the efficiency of the volumetric flow into the combustion chambers increases dramatically. This is one reason why a vehicle gets better mileage on the freeway than in the city. An EGR valve that is stuck open, a leaking intake manifold gasket, a defective mass air flow sensor, a weak or failing fuel pump, or a plugged fuel filter are some of the many causes for a lean misfire.

Mechanical Misfire:

Mechanical problems can also cause an engine to misfire. Common causes of a mechanical misfire are—worn piston rings, cylinder walls, or lobes on a camshaft, a leaking head gasket or intake manifold gasket, damaged or broken rocker arms, defective fuel injectors (and/or the electronics that control them), and a slipped or incorrectly installed timing belt or timing chain. Generally, this type of misfire has more of a regular thumping type of feel to it. It is usually noticeable regardless of engine speed; in fact, it may even intensify as the engine speed increases.
Sometimes a vehicle may misfire or run poorly and it has nothing to do with the operation of the engine. One common cause for "jerky" performance from the power train is a problem in the transmission and its ability to properly shift. If the misfire is at higher speeds, it could be a problem with the operation of the overdrive gear or a chattering clutch in the lockup torque converter. Make sure you have the vehicle properly inspected for the misfire. Entire engines have been replaced to solve a problem that was actually rooted in the transmission—much to the chagrin of the owner and the repair shop.

Price range for fixing of Misfiring: £0.00 - £0.00


Return to the top of the page
What Is Engine Knocking?


Engine knocking refers to the metallic sound an engine can produce when pressure is applied to the gas pedal. The noise may be a hollow knocking sound or it can be more of a rattling type sound in either case, it's not a sound you want to hear.

When an engine knocks, it releases pollution into the environment in the form of nitrogen oxide (NOx) and raw, unburned hydrocarbons (HCs). These two chemicals are poisonous gases that show up as yellowish-brownish in a polluted sky. They can also cause respiratory problems like asthma and emphysema a knocking engine is never a good thing.

There are some common causes for an engine to make these sounds.

Incorrect Combustion Process

An engine can knock because the combustion process is incorrect in some way. A "spark knock" is the result of combustion occurring too early. In a properly firing cylinder, the flame front starts on one side of the piston and burns across the top to the other side, which creates a rapid and evenly-expanding gas that pushes down on the top of the piston. When the combustion process occurs too early, there is a random explosion in multiple locations on top of the piston; when this occurs, the flame front inside the cylinder collides with itself and does not burn evenly. An ignition timing that is too far advanced from the proper specification will create a spark knock because the combustion is initiated too early.

An engine can knock because it is too hot; this is another uneven combustion scenario that is caused by the air to fuel mixture "lighting off" by itself. If the cooling system does not keep the engine's combustion chamber temperature in check, the air to fuel mixture will begin to spontaneously explode. This is called "pre-ignition" or "pinging."

In addition to cooling system problems, pinging can be caused by improper fuel octane, an overly lean air to fuel mixture, or a lack of proper exhaust gas recirculation. The exhaust gas recirculation system (EGR) was created to neutralize engine knocking by adding a small amount of exhaust gas to the air to fuel mixture going in to the combustion process, which limits the peak combustion chamber temperature.

Internal Mechanical Problems

Internal mechanical problems can also cause engine knocking. One such problem stems from excessive clearance inside the bearings in the connecting rods that transfer the downward movement of the pistons to crankshaft rotation. Each time the piston changes direction, there is a knock from the metal hitting metal. This is often referred to as a "rod knock." It is usually very rhythmic; it increases with engine speed and intensifies with engine load.

Other mechanical problems that lead to engine knocking are:

* Defective main crankshaft bearings.

* A cracked or broken flywheel or flex-plate that attaches the engine to the transmission.

* A worn water pump bearing.

* A failed or loose timing belt tensioner can knock when the timing belt slaps against it.

* An air conditioning compressor can knock when it is failing or icing up.

* An alternator with worn rotor bearings can knock when the pistons fire.

Be sure to properly inspect and verify the root cause of the knocking sound, as it can be tricky to pinpoint. You don't want to replace the entire engine only to find out that the knocking was coming from a cracked hub on the transmission flywheel or flex-plate. Ouch!

Price range for Fixing a Knock Engine: £0.00 - £0.00 (May require new engine)


Return to the top of the page
What Is Engine Pinging?


"Pinging" is the rattling sound an engine can make when accelerating. It usually occurs when the vehicle pulls away from a stop and the engine is under a lot of load or is "lugging" This is not a normal condition or desirable condition.

Here are some common reasons for an engine to ping.

An engine can ping because the combustion process is incorrect in some way. A "spark knock" is the result of combustion occurring too early. In a properly firing cylinder, the flame front starts on one side of the piston and burns across the top to the other side, which creates a rapid and evenly-expanding gas that pushes down on the top of the piston. When the combustion process occurs too early, there is a random explosion in multiple locations on top of the piston; when this occurs, the flame front inside the cylinder collides with itself and does not burn evenly. An ignition timing that is too far advanced from the proper specification will create a spark knock because the combustion is initiated too early.

An engine can ping because it is too hot; this is another uneven combustion scenario that is caused by the air to fuel mixture "lighting off" by itself. If the cooling system does not keep the engine's combustion chamber temperature in check, the air to fuel mixture will begin to spontaneously explode. This is also called "pre-ignition."

In addition to cooling system problems, pinging can be caused by improper fuel octane, an overly lean air to fuel mixture, or a lack of proper exhaust gas recirculation. The exhaust gas recirculation system (EGR) was created to neutralize engine pinging by adding a small amount of exhaust gas to the air to fuel mixture going in to the combustion process, which limits the peak combustion chamber temperature.

When an engine pings, it releases pollution into the environment in the form of nitrogen oxide (NOx) and raw, unburned hydrocarbons (HCs). These two chemicals are poisonous gases that show up as yellowish-brownish in a polluted sky. They can also cause respiratory problems like asthma and emphysema-a pinging engine is never a good thing.

Price range for fixing a Pinging Engine: £0.00 - £0.00


Return to the top of the page
Why Are My Brakes Making Noise?


Brakes are a critical component of your vehicle. If you experience any diminished performance when applying the brakes or have warning lights indicating a brake problem with your vehicle it may not be safe to continue driving your car. You should have brake work carried out by qualified mechanics.

What's the noise? How severe is the problem??

Determine under what conditions and from what area of the vehicle you hear noise. Do you experience the noise only during the first few brake applications in the morning? Do you hear the noise when braking at higher speeds, or during gently brake applications? Does the noise appear to be a grinding sound, clunking sound, or a higher pitched squeal? Does it appear to come from the front or rear of the vehicle?

Noise heard while braking is an indication of brake wear and the brakes should be inspected. Brakes are very much a safety item, and delaying repair is not a safe strategy. In fact, delaying repair can potentially lead to more expensive repairs because worn brake pads can wear down to the metal backing. When the squealing turns into a grinding, the brake rotors are likely being damaged (often requiring replacement).

What's that squealing? How do I know my brakes should be inspected?

Before we assume the brake pads are worn, it’s important to understand that overheating brakes can cause a light speaking, especially when the brakes are still cold. If there is sufficient pad material remaining, heat is a possible cause for squeaking.

Many car manufacturers incorporate some form of early warning system to alert the driver that the brakes need service. European cars typically use a warning light on the instrument cluster to alert the driver when it is time to replace the brake pads. A sensor mounted to the brake pad wears when the pad is worn to the minimum allowable thickness and the warning light illuminates. Sensors are normally replaced when the brake pads are replaced.

Many Asian and American cars have a metal "finger" (sensor) that is an integral part of the brake pad. As the pad wears down, the sensor contacts the rotating brake disc (rotor) creating a high pitched squealing sound almost comparable to running your fingers down a chalk board. Brakes should be periodically inspected for wear and replaced as required; you should not rely on the visual or audio warning as your means of assurance that your brakes are OK.

Continually driving a car until the friction lining of the brake pads are worn away will lead to expensive damage and your brakes may fail. Anytime the brakes make an abnormal noise they should be inspected and repaired before the braking system becomes compromised in any way.

Brake Pulsations! What does that mean anyway??

Sometimes pulsations can be subtle and only your passengers notice. They might even be annoyed because they think you're tap-tap-tapping the brake pedal. Pulsations can be felt when you hold consistent pressure on the pedal but the vehicle does not slow down smoothly. Sometimes this can even feel like the brake pedal is pushing back on your foot!

The surfaces of the brake rotors must be flat, smooth and both sides of each brake rotor must be parallel to each other (uniform thickness). This minimizes brake noise or brake pedal vibration when the brakes are applied. If the braking surface is not parallel to the wheel mounting surface, the brake rotor is considered to be warped. If the brake rotor is warped and/or no longer parallel, the brake rotor can be machined provided it is sufficiently thick enough to have material removed. There is a minimum allowed thickness specification for brake rotors. The brake rotors are accurately measured for thickness variation and "run out" to determine if they will be serviceable after they are machined.
What are my options?

Brake linings are a maintenance item and are designed to wear. There are three main types of brake pads available for your vehicle. The different friction (stopping) materials, organic, semi-metallic, and ceramic, each have their own characteristics. When it's time to replace your brake pads or shoes discuss with your shop or parts supplier your driving habits and how you use your vehicle. Original equipment brake pads from the dealer are always a good option if you have been satisfied with the braking performance. You won't usually have the same amount of options from a dealer but you can be sure you will be buying a quality brake pad set.

Brake pads generally have silencing shims fitted to them to dampen vibrations and/or locate the brake pads in the brake calliper. If the silencing shims and other brake hardware are assembled incorrectly, missing or damaged you may experience an abnormal noise when the brakes are applied.
A little background.

All modern cars have disc brakes in the front. The brake rotor is like the rim of a bicycle, it rotates with the tire and wheel. When the brakes are applied, the brake pads put clamping pressure on the brake rotor in the same manner the rubber brake blocks come in contact with the rim of a bicycle. Pressure the brake pads apply to the brake rotor is proportional to the pressure applied to the brake pedal by the driver.

Brake pads wear depending on driving habits and vehicle use. Front brake pads typically wear two to three times quicker than the rear brake linings. Vehicles equipped with automatic transmissions tend to wear brakes out a little quicker than a vehicle with a manual transmission.

Price range for fitting of Brake Pads: £0.00 - £0.00
###### Break Discs: £0.00 - £0.00


BRAKES


Return to the top of the page
Anti-Lock Brake System


The purpose of an Anti-Lock Brake System is to prevent the loss of tire to road traction during braking. This is accomplished by the use of an Anti-Lock Computer System that precisely monitors individual wheel speed sensors and then adjusts the amount of braking force applied to the each wheel based on this and other monitored data points.

Brake System Maintenance

Most of us don't think about our car's brakes until we need them for a panic stop; hear a screeching or grinding noise, or when a warning light comes on. But brakes are worn down every time you drive your car. It's important to keep them maintained and serviced—before you hear that screeching. The sooner the better ... and cheaper.

All cars incorporate some type of brake warning system to inform the driver of a problem. A warning light is the most common. It typically alerts a driver to:

* Low brake fluid.

* Brake system hydraulic pressure failure.

* An applied parking brake.

* An ABS malfunction.

* Brake pads need replacement.

* An inoperative brake bulb.

Some systems have metal clips that rub on the rotors when pads are worn out. This causes a high-pitched, fingernails-on-a-chalkboard screech when the brake pedal is pressed. Some newer vehicles alert the driver in a more civilized and agreeable manner with warning lights or computerized messages. No matter which your vehicle has, it's critical to address the issue promptly.

Price range for Labour of Fitting Anti Lock Brakes: £0.00 - £0.00


Return to the top of the page
ABS Control Module Replacement


The antilock brake control module counts the number of revolutions each wheel makes to determine whether the brake at each wheel is operating correctly or if it has locked up. If the brakes lock up, the antilock brake control unit releases the brake pressure applied to each wheel until the unit determines whether each wheel is contributing the correct amount of braking effort.

The ABS control module is located either in the passenger compartment of the vehicle behind the dashboard or in the engine compartment. To replace the control module, a technician unplugs and removes the old one and replaces it with the new control module. On newer vehicles, the module may need to be "programmed" before the vehicle is driven.

Antilock brakes (ABS) are a safety feature that prevent the wheels from locking up while braking. If a wheel locks up during braking, it no longer helps to stop the vehicle.

Brake fluid naturally absorbs moisture from the surrounding air. Moisture is the enemy of any hydraulic system; it lowers the operating efficiency of the brake system and may result in costly repairs if not periodically replaced.

Mechanics Corner: More Technical Detail

The ABS control unit only releases the brake pressure to the particular wheel that is locking up; wheels that are not locking up will not be affected.

The first step in replacing any onboard computer like an ABS module is to disconnect the battery. If you replace any control unit with the battery connected, there is a real possibility that the control unit will be damaged from an electrical surge or 'spike'.
About this Repair: ABS Control Module Replacement
Why this happens

* A failing ABS control module can cause the ABS light on the dashboard to come on.

* A malfunctioning ABS Control Module can cause abnormal braking behaviour or problems with the ABS system.

* A loose or worn connection to ABS Control Module can turn on an ABS dashboard light.

* It may be appropriate to flush the brake system with new fluid when replacing the ABS Control Module.

Price range for Fitting ABS Control Module Replacement: £0.00 - £0.00


Return to the top of the page
ABS Wheel Speed Sensor Replacement

Sometimes referred to as ABS Wheel Speed Sensor, Wheel Speed Sensor, Speed Sensor, Antilock Brake Sensor, Anti-lock Brake Sensor, Anti-lock Sensor, Antilock Sensor, ABS Wheel Sensor, Wheel Sensor, ABS Wheel Speed Sensor Replacement, Wheel Speed Sensor Replacement, ABS Wheel Sensor Replacement

An antilock brake wheel speed sensor measures the speed of each wheel by counting the number of revolutions each wheel makes while breaking to be sure the wheel isn't locking up. If a wheel locks up, the antilock brake control module can apply or release brake fluid pressure to each wheel, releasing the wheel from its locked state.

To replace the ABS wheel speed sensor, the wheel is removed. The sensor is then found near the wheel bearing hub. The sensor is electrically disconnected, removed, and replaced with the new component. In some vehicles the sensor is incorporated with the hub assembly and the entire hub assembly must be replaced.

The wheel speed sensors are reliable but may be damaged if they come into contact with road debris.
About this Repair: ABS Wheel Speed Sensor Replacement
What to watch out for:

* ABS wheel speed sensors can be easily damaged during other repairs that call for the wheels to be removed. If you have had recent repair work performed, return the vehicle to the shop to inspect for damage.

Recommendations:

* Many conditions, including corrosion, worn bearings, or other problems in ABS system can set a wheel speed sensor trouble code. Any problem with the ABS system needs to be diagnosed before wheel speed sensors are replaced, as a new sensor may not solve the problem.

Why this happens

* A failed wheel speed sensor can cause the ABS light on the dashboard to come on.

* Malfunctioning wheel speed sensors can cause abnormal braking behaviour or problems with the ABS system.

Price range for ABS Wheel Speed Sensor Replacement: £0.00 - £0.00


Return to the top of the page
Bleed Brake System


The brake system requires brake fluid that is free from any air bubbles. Because the brakes are operated through hydraulic pressure, air bubbles in the fluid can compress and reduce the force applied to the brakes.

Air bubbles can enter the brake system during normal repairs (such as a brake calliper replacement). Bleeding or flushing out the brake fluid removes any air bubbles from the brake fluid. The modern method uses an appliance known as a brake bleeder. The brake bleeder introduces fresh brake fluid under pressure to the brake fluid reservoir.

The brake bleeder screws (located at each brake calliper) are manually opened in succession, allowing fresh fluid to flow through that branch. The screws are opened in the following order: right rear, left rear, right front, left front until all four are filled with fresh brake fluid. This process not only fills the reservoir with fresh brake fluid, but also naturally purges and displaces any trapped air, thus "bleeding" the brakes.

Flushing the brake fluid is recommended at time or mileage intervals, based on the manufacturer's recommended maintenance schedule. In most modern vehicles, the brake fluid level is monitored via a sensor in the brake fluid reservoir. Changes in the brake fluid level are displayed on the instrument panel as an indicator of normal brake wear. As the brake pads or brake shoes wear, the brake fluid level will correspondingly drop from maximum to minimum levels. When the brake fluid level nears minimum—and the low-fluid display activates—the brakes should be inspected for wear before adding brake fluid. If the brakes are not worn and the fluid level is low, there may be a leak. Inspect and repair accordingly.

Recommendations:

* Brake fluid should be replaced if the fluid is dirty or shows any evidence of rust or corrosion in the brake system.

* Brake fluid absorbs moisture and loses effectiveness over time. We recommend that the fluid be replaced every two years as preventative maintenance.

Price range for Bleeding Break Fluid: £0.00 - £0.00


Return to the top of the page
Brake Calliper Replacement


Disc brakes are commonly used on each wheel of a modern car’s braking system. Brake callipers are part of a disc brake system.

Brake pads are located in the brake calliper. When pressure generated by the brake master cylinder is applied to the brake calliper, it distributes brake pressure to the brake pads. The brake pads are brought in contact with the brake rotor (disc). The more pressure generated in the brake calliper, the more braking pressure is applied to the brake pads. The greater the level of pressure applied to the brake pads, the sooner a vehicle stops.

Brake callipers operate in much the same way that brakes on a bicycle work. Instead of mechanically pulling a cable to get rubber blocks to come in contact with the rim of the bicycle tire, hydraulic pressure pushes brake pads into contact with a brake rotor (disc).

To replace a brake calliper, the wheel is removed and the defective brake calliper is taken off the vehicle. We recommend replacing brake callipers as a pair to maintain optimum operating efficiency. After replacing the brake calliper, air must be removed from the brake system to enable it to function correctly.

Price range for Brake Disc Replacement: £0.00 - £0.00


Return to the top of the page
Brake Drum Remachine / Resurface


If the driver feels vibration in the brake pedal while braking, it may indicate that the brake drums need to be remachined or replaced.

To remachine, or resurface, brake drums, the technician removes the brake drums from the vehicle and machines them on a lathe. Brake drums need to be remachined if the vehicle has been driven with worn-out brake linings or if the drums have become damaged by heat (which may result in a vibration when the brakes are applied). When brake drums are remachined, damaged material is removed.

There is a maximum amount of damaged material that can be removed before the brake drums are deemed not serviceable and must be replaced.

Price range for Brake Drum Replacement: £0.00 - £0.00


Return to the top of the page
Brake Drum Replacement


Brakes are located at each wheel to enable the vehicle to slow and stop.

A few modern cars still use drum brakes and, almost without exception, drum brakes are used on the rear wheels. The brake drum is attached to the wheel and rotates along with it. When the brakes are applied, brake shoes are pressed into contact with the brake drum, slowing the vehicle. The harder the brakes are applied, the more firmly the brake shoes are pressed against the brake drums, which makes the car stop faster.

A technician must remove the wheel to replace the brake drum. After the brake drum is removed, brake components are inspected for wear or damage. After the new brake drum is installed, the wheel is put back on and the brakes adjusted.

Brake shoes wear out over time and should be inspected periodically. Brake performance will be compromised if the brake shoes become contaminated with brake fluid or oil due to leaky seals or wheel cylinders.

Price range for Labour Fitting of Brake Drum Replacement: £0.00 - £0.00


Return to the top of the page
Brake Flexible Hose Replacement


A flexible portion of the otherwise rigid metal brake line is needed to allow the front wheels of the vehicle to move freely as the vehicle is steered and to allow the up-and-down motion at the rear wheels. These flexible brake hoses attach the rigid, metal brake line to the callipers at the four wheels.

Flexible brake hoses may require replacement due to visible cracks, leaks, or damage. The flexible brake hose may become blocked internally due to swelling or contamination. This internal blockage may not be visually evident, but may cause uneven braking such as pulling left or right while braking or it may feel like the brakes are slightly applied or dragging when the vehicle is moving. In extreme cases, the brake pedal effort will feel normal, but the vehicle will not stop as it should.

Recommendations:

* When replacing a brake flexible hose due to internal blockage, be sure to replace all the brake flexible hoses at the same time. Replacement is usually straightforward.

* Brake fluid replacement or brake bleeding is required.

Price range for Labour Fitting of Brake Drum Replacement: £0.00 - £0.00


Return to the top of the page
Brake Fluid Replacement


Brake fluid replacement is a brake bleeding procedure. The modern method uses an appliance known as a brake bleeder. The brake bleeder introduces fresh brake fluid—under pressure—to the brake fluid reservoir.

The brake bleeder screws (located at each brake calliper) are manually opened in succession, allowing fresh fluid to flow through that branch. The screws are opened in the following order: left rear, right rear, right front, left front until all four are filled with fresh brake fluid. This process not only fills the reservoir with fresh brake fluid, but also naturally purges and displaces any trapped air, thus "bleeding" the brakes.

In most modern vehicles, the brake fluid level is monitored via a sensor in the brake fluid reservoir. Changes in the brake fluid level are displayed on the instrument panel as an indicator of normal brake wear. As the brake pads or brake shoes wear, the brake fluid level will correspondingly drop from maximum to minimum levels. When the brake fluid level nears minimum—and the low fluid display activates—the brakes should be inspected for wear before adding brake fluid. If the brakes are not worn and the fluid level is low, there may be a leak. Inspect and repair accordingly.

Brake fluid will damage a vehicle's paint, so avoid contact with the surface of the car.

Price range for Labour of Brake Fluid Replacement: £0.00 - £0.00


Return to the top of the page
Brake Master Cylinder Replacement


The brake master cylinder generates hydraulic pressure necessary to slow down or stop a vehicle. The master cylinder is located in the engine compartment.

When the brake pedal is applied, the brake master cylinder generates hydraulic pressure, which is then distributed to each wheel. This pressure then engages either the brake pads or brake shoes to slow down or stop the vehicle.

To replace the brake master cylinder, brake fluid is removed from the brake fluid reservoir. Then the brake lines are removed from the master cylinder. After the new brake master cylinder is installed, brake fluid is added to the reservoir. A brake bleeder screw is opened at each wheel, and the brake pedal is continually depressed until fresh brake fluid exits at all wheels.

Brake fluid naturally absorbs moisture from the surrounding air. Moisture is the enemy of any hydraulic system; it lowers the operating efficiency of the brake system, and it may result in costly repairs if the brake fluid is not periodically replaced. The brake system is sealed and should not require frequent topping up. If the brake fluid does require frequent topping up, the brake system has a leak that must be investigated.
About this Repair: Brake Master Cylinder Replacement

Recommendations:

* Problems elsewhere in the brake system can cause symptoms similar to a defective brake master cylinder, including seals and ABS valve bodies. Have the shop inspect the entire brake system to verify that the problem is specific to the master cylinder.

* Flushing brake fluid at least every two years can extend the life of brake master cylinders.

Why this happens:

* A failing brake master cylinder can cause a "spongy" or "sinking" brake pedal that is not very responsive while braking and stopping.

* A defective brake master cylinder can set a trouble code and cause a warning light on the dashboard to illuminate.

* Brake master cylinders are often replaced because they have begun to leak brake fluid.

Price range for Labour of Brake Master Cylinder Replacement: £0.00 - £0.00


Return to the top of the page
Brake Pads Replacement


Brake pads are located in the brake callipers at each wheel. Each time the brakes are applied, brake pad material wears down.

As the brakes are applied, brake pads come into contact with the brake rotor to slow the vehicle down. The brake rotor (or disc) is comparable to the rim of a bicycle tire. And as with a bicycle, the harder the brakes are applied, the quicker the vehicle stops.

Brake pad material wears out over time. Brake pads should be periodically inspected for wear, which is highly variable and depends on vehicle weight and driver habits. Brake pads must be replaced before the friction material is worn away completely. If it isn't, metal-to-metal contact will occur between the brake rotor and the worn-out brake pad. If metal-to-metal contact occurs, the brake rotor will be damaged. It will then need to be resurfaced or replaced.

To replace the brake pads, the wheel is removed to gain access to the brake callipers. The brake pads are withdrawn from the brake callipers, and the callipers, brake hardware, and brake rotors are inspected for damage and wear.
About this Repair: Brake Pad(s) Replacement

Recommendations:

* The brake rotors should be inspected when the pads are replaced, and may need to be replaced or resurfaced.

* Shops will often refer to brake pad wear as a percentage of material remaining. Ask the shop to be specific about how much of the pad is remaining. We recommend that brake pads are replaced when there is 20% or less material remaining.

* We recommend braking gently for the first 40 to 50 miles of driving on new pads. This will allow them to adjust to the rotors and may help prevent squeaking.

Why this happens:

* Worn brake pads often result in a loud squeaking or grinding noise while driving, especially at low speeds. Replacing your brake pads early may prevent the brake rotors from being worn or damaged beyond repair.

* Brake pads will wear out more quickly as they age. The second half of a brake pad will wear away more quickly than the first.

Price range for Labour of Brake Pads Replacement: £0.00 - £0.00


Return to the top of the page
Brake Rotor Re-Machine


Brake rotors may need to be remachined if they have become damaged by heat generated during braking or if the vehicle has been driven with worn-out brake pads.

Vibration felt in the brake pedal or steering wheel while braking may indicate that the brake rotors need to be remachined or replaced.

On many front wheel–drive vehicles, the brake rotors can be machined while they are still on the vehicle. Other vehicles' brake rotors must be removed from the vehicle to be remachined.

Remachining brake rotors means that damaged material is removed. There is a maximum amount of damaged material that can be removed before the brake rotors are deemed not serviceable and must be replaced. Brake rotors removed from the vehicle are remachined on a lathe. Vehicles whose brake rotors can be machined while still on the vehicle are serviced using a portable brake lathe.

On some vehicles, it is not recommended to remachine brake discs at all.

Price range for Labour of Brake Remachine: £0.00 - £0.00


Return to the top of the page
Brake Rotor/Disc Replacement


Brakes are located at each wheel to slow or stop the vehicle.

Brake pads apply pressure to the brake rotors to slow or stop the vehicle. The brake rotor (or disc) is comparable to the rim of a bicycle tire. As the brakes are applied, brake pads come into contact with the brake rotor to slow the vehicle down. As with a bicycle, the harder the brakes are applied, the quicker the vehicle stops.

Brake pad material wears out over time. Brake pads should be periodically inspected for wear, which is highly variable depending on vehicle weight and driver habits. Brake pads must be replaced before the friction material is worn away completely. If it isn't, metal-to-metal contact will occur between the brake rotor and the worn-out brake pad. If metal-to-metal contact occurs, the brake rotor will be damaged, and it will need to be resurfaced or replaced.

The brake rotor is attached to the wheel, which must be removed to gain access to the brake rotor. The brake calliper must then be removed. In some cases, the wheel bearings may also need to be removed. To maintain optimum brake-operating efficiency, replace brake rotors as a set.

Price range for Labour of Brake Disc Replacement: £0.00 - £0.00


Return to the top of the page
Brake Shoes Replacement


Brakes are located at each wheel to enable the vehicle to come to a complete stop.

Drum brake systems are generally used on the rear of modern vehicles. The brake drum is attached to the wheel and rotates along with it. As the brakes are applied, brake shoes are pushed into contact with the brake drum, slowing the vehicle. The harder the brakes are applied, the more firmly the brake shoes press against the brake drums, resulting in the vehicle stopping in a shorter distance. Brake shoes wear each time the brakes are applied.

To replace the brake shoes, the wheel is removed. Then the brake drum is removed, exposing the brake shoes. The wheel cylinders are inspected for leaks, and the brake drums and brake hardware are examined for damage. After replacing the brake shoes and reassembling the related brake components, the brakes are adjusted and the technician drives the vehicle to ensure the brakes are working correctly.

Brake shoes wear out over time and should be inspected periodically. Brake performance will be compromised if the brake shoes become contaminated with brake fluid or oil due to leaky seals or wheel cylinders.
About this Repair: Brake Shoe(s) Replacement

Recommendations:

* We recommend resurfacing the brake drums when the brake shoes are replaced, so that the components perform optimally.

Why this happens:

* Brake shoes can be damaged by defective drums, and can also be ruined by fluid leaks.

* Brake shoes are a regular maintenance item that needs to be replaced when they wear out.

Price range for Labour of Brake Shoe Replacement: £0.00 - £0.00


Return to the top of the page
Parking Brake Shoes Replacement


Motor vehicles have two separate brake systems. One stops or slows down the vehicle when the brake pedal is applied; the second is operated mechanically by the driver when the car is stationary or parked.

The parking brake system may mechanically apply the brake shoes of the conventional brake system, or it may operate a set of parking brake shoes. These shoes are located in a brake drum and are integrally cast in the centre of the brake rotor. The brake rotor is attached to the wheel. When the parking brake is applied, the vehicle is mechanically prevented from moving.

The parking brake is applied by manually pulling a lever or depressing a parking brake pedal inside the vehicle. The parking brake should be disengaged before putting the vehicle in gear.

To replace the parking brake shoes, the rear wheels, rear brake callipers, and brake rotors must be removed. The parking brake shoes are replaced, all related brake components are reassembled, and finally, the parking brake is adjusted.

Brake shoes wear out over time and should be inspected periodically. Brake performance will be compromised if the brake shoes become contaminated with brake fluid or oil due to leaky seals or wheel cylinders.

Price range for Labour of Parking Brake Shoes Replacement: £0.00 - £0.00


Return to the top of the page
Rear Brake Calliper Replacement


Disc brakes are commonly used on each wheel of a modern car’s braking system. Brake callipers are part of a disc brake system.

When the driver depresses the brake pedal, pressure generated by the brake master cylinder is applied to the brake calliper. It in turn distributes brake pressure to the brake pads. The brake pads are brought into contact with the brake rotor (disc). The more pressure generated in the brake calliper, the more braking pressure is applied to the brake pads. The greater the level of pressure applied to the brake pads, the sooner a vehicle stops.

Brake callipers operate in much the same way as brakes on a bicycle. Instead of mechanically pulling a cable to get rubber blocks to come in contact with the rim of the bicycle tire, hydraulic pressure pushes brake pads into contact with a brake rotor (disc).

To replace the rear brake calliper, the wheel is removed and the defective brake calliper is taken off the vehicle. We recommend replacing both rear brake callipers to maintain optimum operating efficiency. After replacing the brake calliper, air must be removed from the brake system to enable the system to function correctly.
About this Repair: Brake Calliper Replacement - Rear

Recommendations:

* We recommend that callipers be replaced in pairs when possible and that the brake system be flushed when callipers are replaced.

* The shop should inspect the entire brake system and should verify that the vehicle stops efficiently and in a straight line.

Why this happens

* Callipers require replacement when they are leaking fluid or if one or more of their component pistons have become stuck.

* A failing brake calliper can cause the vehicle to pull to one side when braking.

Price range for Labour of Rear Brake Calliper Replacement: £0.00 - £0.00


Return to the top of the page
Wheel Bearing Replacement


Wheel bearings allow each wheel to rotate. There are several types of wheel bearings used in automobiles. Some require no maintenance; others can be disassembled, cleaned, and inspected for wear.

Failing wheel bearings develop excess clearance, or play. One symptom that may develop when the bearing is put "under load" is a distinctive growling noise that can be heard when the wheels are rotating at road speeds.

Wheel bearings are located in the brake drum or brake rotor. Replacing wheel bearings requires the wheel to be removed. Then the brake drum or brake disc is removed, and the wheel bearings are replaced and packed with fresh grease. The wheel bearing may be an integrated part of the vehicle's suspension. If so, the suspension or wheel hub may need to be removed from the vehicle to replace the wheel bearing.
About this Repair: Wheel Bearing Replacement

Recommendations:

* All related wheel bearings seals should also be replaced.

Why this happens

* Failing wheel bearings can cause a "rumbling" noise while turning and while driving at speeds greater than 15 miles an hour.

* Wheel bearings need to be replaced if they are found to be worn or leaking during related repairs or inspections.

Price range for Labour of Wheel Bearing Replacement: £0.00 - £0.00


Return to the top of the page
Wheel Bearing Service


Wheel bearings allow each wheel to rotate. There are several types of wheel bearings used in automobiles. Some require no maintenance; others can be disassembled, cleaned, and inspected for wear.

Failing wheel bearings become loose and develop excess clearance, or play. One symptom that may develop when the bearing is put "under load" is a distinctive growling noise that can be heard when the wheels are rotating at road speeds.

To service vehicles with serviceable wheel bearings, the wheel must be removed. Then the bearings, brake drum, brake rotor, or wheel hub assembly is removed. The wheel bearings are removed, cleaned, and inspected. If they are OK, they are packed with fresh grease and re-installed. If they show signs of wear, they need to be replaced.

The wheel bearing may be an integrated part of the vehicle's suspension. If so, the suspension or wheel hub may need to be removed to replace the wheel bearing.

Price range for Labour of Wheel Bearing Check: £0.00 - £0.00


Return to the top of the page
ABS Control Module


The ABS control module monitors the electrical signals generated by the ABS wheel speed sensors to determine how fast the wheels are slowing down during braking. If the ABS control module determines that a wheel is slowing too rapidly, it intervenes by modulating the brake pressure to that wheel; this prevents the wheel from locking up. A wheel that is locked up or not rotating has lost traction and cannot be steered. The ABS control module continuously performs diagnostic self-checks.


Return to the top of the page
ABS Pump


The term "ABS Pump" usually describes a combination assembly that consists of an electric brake fluid pump and a solenoid controlled valve body that either releases or builds brake system pressure to the individual wheels, depending on the commands it receives from the ABS computer.


Return to the top of the page
ABS Wheel Speed Sensor


An anti-lock brake system (ABS) wheel speed sensor measures the speed of each wheel. Each wheel usually has one sensor, but some vehicles have one sensor for both rear wheels. The ABS wheel speed sensor utilizes a stationary electrical sensor that is located in close proximity to the rotating area of the wheel or axle; this electrical sensor generates an analogue signal that corresponds to the wheel's actual speed.


Return to the top of the page
Brake Booster


The brake booster—installed between the brake pedal and the brake master cylinder—unobtrusively assists the driver's braking efforts by providing a safe and proportionate level of effort when the brakes are applied.

Though some brake boosters are purely hydraulic in function, the almost-universal design incorporates a servo mechanism that utilizes the vacuum produced by the engine—and often a boost pump—to assist in application of the brakes.

Brake boosters are normally quite reliable; however, failures can occur. The booster is rarely the issue though; problems in the vacuum supply plumbing and valves or water intrusion are more likely culprits. On newer vehicles, complications can arise from the vacuum boost pump.

By design, brake booster failure will not cause the brakes to fail. The driver will notice an increased braking effort is needed, but otherwise, braking will not be affected.


Return to the top of the page
Brake Calliper


The brake calliper applies pressure to the brake pads with hydraulic pressure from the master cylinder. Hydraulic brake fluid travels through the brake hose to the calliper and activates a piston that pushes the brake pads against the brake rotor.


Return to the top of the page
Brake Calliper Pins


Brake Calliper Pins are the 2 round metal guide pins on which the brake calliper piston assembly rides. They allow the piston assembly to move in or out a bit while still maintaining or "guiding" the proper brake pad to rotor angle for the most efficient braking.


Return to the top of the page
Brake Drum


Drum brake systems are generally used on the rear of newer vehicles. A brake drum is mounted behind each wheel and rotates along with it.


Return to the top of the page
Brake Flexible Hose


The flexible brake hoses transfer brake fluid pressure to braking components at each wheel. A flexible portion of the otherwise rigid metal brake line is needed to allow the front wheels of the vehicle to move freely as the vehicle is steered and to allow the up-and-down motion at the rear wheels. These flexible brake hoses attach the rigid, metal brake line to the callipers at the four wheels.


Return to the top of the page
Brake Flexible Hose Sealing Washer


The brake flexible hose sealing washer provides a seal that prevents leakage, contains pressure, and excludes contamination. The washer is located where the braking components at each wheel join together.


Return to the top of the page
Brake Fluid


Brake fluid transmits hydraulic force to various parts of the braking system when the brake pedal is pressed. The brake fluid in your vehicle is a serviceable item that needs to be replaced at intervals determined by the manufacturer.


Return to the top of the page
Brake Hydraulic System


The brake hydraulic system transmits the force needed to provide braking action. It consists mainly of the master cylinder, brake lines and hoses, brake callipers, wheel cylinders, and brake fluid.


Return to the top of the page
Brake Master Cylinder


When the brake pedal is applied, the brake master cylinder generates hydraulic pressure that is then distributed to each wheel.


Return to the top of the page
Brake Pad Set


As the brakes are applied, brake pads come into contact with the brake rotor to slow the vehicle down.


Return to the top of the page
Brake Pad Wear Sensors (Electrical)


Electrical Brake Pad Wear Sensors are little plastic sensors (shaped square or round) that are usually installed inside the Brake Pad friction material that contain one or more wires that connect to the Brake Pad Warning System in the Instrument Cluster. When the Brake Pad wears to a specified point, the plastic covering the wire(s) becomes exposed and touches the metallic rotor which signals the Instrument Panel to warn the driver that the Brake Pads have reached their wear limit.


Return to the top of the page
Brake Pad Wear Sensors (Metallic)


Metallic Brake Wear Sensors are thin metal blades that are mounted on the brake pads. When the pads wear down to a pre-determined thickness, the metal blades scrape the rotor and make a screeching sound that warns the vehicle driver that the brake pads are thin and need replacing.


Return to the top of the page
Brake Pads


As the brakes are applied, the brake pads grip the rotating wheel (via the brake rotor) to slow down the vehicle. Brake pads are made of a thick composite lining, much like the heel of a shoe, and are the wear point of the brake system.


Return to the top of the page
Brake Rotor


The brake rotor (or disc) is comparable to the rim of a bicycle tire. As the brakes are applied, the brake calliper squeezes brake pads into contact with the brake rotor to slow the vehicle down.


Return to the top of the page
Brake Rotor Pair


The brake rotor (or disc) is comparable to the rim of a bicycle tire. As the brakes are applied, brake pads come into contact with the brake rotor to slow the vehicle down.


Return to the top of the page
Brake Shoe Set


As the brakes are applied, the wheel cylinders push brake shoes out to contact the inside of the brake drum. The resulting friction slows the vehicle.


Return to the top of the page
Front Brake Calliper


The brake calliper applies pressure to the brake pads with hydraulic pressure from the master cylinder. Hydraulic brake fluid travels through the brake hose to the calliper. The calliper then activates a piston that pushes the brake pads against the brake rotor.


Return to the top of the page
Grease


Grease is a lubricant with a higher viscosity than engine oil. Grease is used to lubricate wheel bearings, steering and ball joints, and universal joints.


Return to the top of the page
Hub Assembly


The hub assembly is a housing attached to the suspension that holds the wheel bearing(s). The brake rotor and wheel are bolted directly to the hub. The hub assembly may also include an ABS wheel-speed sensor or sensor ring.


Return to the top of the page
Parking Brake Shoes


Parking brake shoes supplement the standard brake system on some vehicles. When the parking brake is applied, the wheels are mechanically prevented from rotating.


Return to the top of the page
Rear Brake Calliper


The brake calliper applies pressure to the brake pads with hydraulic pressure from the master cylinder. Hydraulic brake fluid travels through the brake hose to the calliper. The calliper then activates a piston that pushes the brake pads against the brake rotor.


Return to the top of the page
Wheel Bearing


The wheel bearing allows the wheel to rotate.


Return to the top of the page
Wheel Bearing Seal


The wheel bearing seal keeps grease in the wheel bearing.


Return to the top of the page
Wheel Cylinder


A wheel cylinder is part of a drum brake system. The cylinder puts pressure on the brake shoes, which in turn contact the brake drum. This causes friction that slows or stops the vehicle.


DRIVE TRAIN

Return to the top of the page
Drive Train


The drive train is a system of components the engine, transmission, drive shafts, geared differentials, and drive axles working together to generate power and deliver it to the wheels.

If you’ve read the engine overview, then you know how a car gets its power. But how does it put that power into the asphalt and move you down the road? Through the drive train. You’ll also hear more specific words, such as power train and driveline. Power train refers to only the engine and transmission. Driveline refers to everything but the engine and transmission.

Related Services & Repairs:
######Clutch Assembly
######Clutch Cable
######Clutch Fluid
######Clutch Master Cylinder
######Clutch Slave Cylinder
######Differential
######Drive Shaft
######Drive Shaft Universal Joints

Although every car has an engine, not all cars put power to the pavement in the same way. There are four ways power can be transmitted.

* Front-wheel Drive. The drive train sits over the front wheels. The transmission and differential are integrated into the transaxle, which is positioned below the engine. Power flows from the engine through the transaxle and to the drive axles which connect to the front wheels.

* Rear-wheel Drive. The engine sends power to the transmission, which is connected to the driveshaft. The driveshaft is connected to a rear differential, which divides the power between the 2 drive axles connected to the rear wheels.

* All-wheel Drive (AWD). Modern AWD vehicles are highly sophisticated. They send power to all four wheels through computer-controlled traction systems. However, they lack a transfer case for low-range gearing, as do 4 wheel–drive vehicles. Some AWD systems don't work full-time: the system turns on only when one of the two axles loses traction.

* 4-wheel Drive (4WD). There are two kinds of 4WD: full-time and part-time. Full-time 4WD has power at all wheels all the time. A differential inside the transfer case allows for smooth power distribution. Part-time 4WD allows either 2-wheel drive or 4WD. But because there’s no differential in the transfer case, only 2WD should be used in dry, non-slippery conditions.

Depending on the drive system, several kinds of drivelines can be used. Rear-wheel and 4WD systems often use drive shafts, long, semi hollow steel tubes with universal joints on either end to enable flexibility. Front-wheel drive and AWD vehicles use solid-steel drive axles with constant velocity (CV) joints on either end. CV joints are highly flexible and help connect the transaxle to the wheel. CV joints have big rubber boots that contain copious amounts of grease, so they are easily identifiable.

The transmission sends power from the engine to the rest of the driveline using a complex set of gears. The transmission allows the vehicle to move from a standing start to more than 100 mph while keeping engine RPMs within a fixed range. The transmission also enables both forward and reverse motion without affecting the engine. Transmissions have evolved a lot over the years, and today there are 3 general types.

* Automatic Transmissions automatically select the ideal gear based on accelerator pedal position, vehicle speed, engine speed, and road conditions. Power from the engine is transmitted through a torque converter, then to the internal gears that shift automatically using hydraulic pressure from the transmission fluid. Automatic transmissions began with just 2 gears, but now there are as many as 8 speeds.

* Manual Transmissions give the driver full shifting control. To change gears, the driver presses a clutch pedal, which disengages the engine from the rest of the drive train, then uses a shifter to change gears. Depressing the clutch pedal generates hydraulic pressure in the clutch master cylinder, which applies the pressure to the clutch slave cylinder and disengages the clutch. A clutch cable performs the same function in older cars. The clutch assembly consists of a clutch disc, a clutch pressure plate, and a clutch release bearing. Since the 1960s, manual transmissions have grown from 3 to 6 speeds.

* Semi-automatic transmission is a relatively new hybrid transmission that combines the driver control of manuals with the driving ease of automatics. Although some semi-automatics use a torque converter with electronic manual shifting buttons, more advanced semi-automatics, from makers such as Audi and Volkswagen, use a clutch disc system for quicker, crisp-performance shifting.


Return to the top of the page
Clutch Assembly, Manual Transmission Replacement


The clutch assembly consists of a clutch disc, a clutch pressure plate, and a clutch release bearing. All these components are usually replaced at the same time. The clutch assembly has two key functions: it transmits power produced by the engine to the gearbox, and it allows that power to be interrupted when the clutch pedal is depressed. Power produced by the engine requires this interruption. It makes it possible to change gears and to shift into neutral at a traffic light or stop sign.

When the clutch assembly is not operating correctly, two things can happen. It either doesn't interrupt the power from the engine to the gearbox, which causes grinding sounds and difficulty in selecting gears. Or it fails to transmit the drive from the engine to the gearbox. This results in the engine “revving up” without the vehicle speed increasing. In the case of a complete failure, the engine will rev up, but the vehicle will not move. Clutch components naturally wear out. Clutch components may fail or wear due to; bad driving habits, being driven with the clutch improperly adjusted, or from exposure to oil.

To replace the clutch assembly, the driveshaft (or half shafts where applicable) and the manual transmission (gearbox) must be removed to gain access to the clutch components. New clutch components are fitted and the gearbox is then reinstalled.

About this Repair: Clutch Assembly Replacement

Recommendations:

* The transmission input shaft should be inspected and replaced along with the clutch if it is defective.

* We recommend that the flywheel always be resurfaced when the clutch is replaced.

Why this happens:

* A failed clutch could either slip or shudder, or be unusually difficult to depress.

* Engine oil or transmission fluid leaks can damage a clutch. When replacing a clutch, any leaks should be diagnosed and repaired to avoid recurring problems.

Price range for Labour of Clutch Replacement: £0.00 - £0.00


Return to the top of the page
Clutch Cable Replacement


The clutch cable provides a means to "break the drive" between the engine and the wheels. The engine spins constantly, but the wheels do not, so in order to stop a car's wheels without turning off the engine, the wheels have to disconnect from the engine. When the clutch pedal is pressed, the cable disengages the plates, allowing the driver to shift gears or coast without killing the engine.

A failing clutch cable may make the clutch pedal difficult to depress. If the clutch cable fails, the clutch pedal may remain on the floor and not return to its normal position.

To replace the clutch cable, disconnect it from the clutch pedal (usually inside the vehicle) and from the release mechanism or cable attachment that operates the clutch assembly (usually at the transmission beneath the vehicle). A new clutch cable is then installed and adjusted. (The specifics vary according to the vehicle and range from straightforward to very difficult.)

About this Repair: Clutch Cable Replacement

Why this happens:

* An incorrectly adjusted or faulty clutch cable can make the clutch pedal hard to depress, even after a full clutch replacement.

Price range for Labour of Clutch Cable Replacement: £0.00 - £0.00


Return to the top of the page
Clutch Fluid Replacement


Clutch fluid is nothing more than conventional brake fluid. It will absorb moisture from the air, so it should be flushed on a yearly or bi-annual basis. Otherwise, the moisture can contaminate and damage the clutch hydraulic system.

To replace the clutch fluid, it is first removed from the clutch fluid reservoir. Then the reservoir is cleaned and fresh fluid is added. The clutch pedal is then pressed and the clutch master cylinder generates pressure, forcing fresh fluid out to the clutch slave cylinder.

Brake fluid will damage a vehicle's paint, so avoid contact with the surface of the car.

Mechanics' Corner: More Technical Detail

If the brake fluid reservoir is shared with the clutch, follow the brake bleeding procedure. However, only the bleed screw at the clutch slave cylinder should be opened to flush out the brake fluid.

If the clutch has a dedicated fluid reservoir, attach the brake bleeder there and proceed as noted above.

Note: Access to the bleeder screw at the clutch slave cylinder can be difficult on some vehicles.

Price range for Labour of Clutch Fluid Replacement: £0.00 - £0.00


Return to the top of the page
Clutch Master Cylinder Replacement


The clutch master cylinder generates the hydraulic pressure necessary to operate the clutch assembly. The clutch assembly has two key functions: to transmit power produced by the engine to the gearbox and to disrupt that power flow when the clutch pedal is depressed.

The clutch pedal is directly attached to the clutch master cylinder. When the clutch pedal is pressed, pressure generated by the clutch master cylinder applies pressure to the clutch slave cylinder. The clutch is then disengaged.

In order for the engine to operate efficiently, a range of gears is absolutely crucial. Power produced by the engine requires the clutch assembly-enabled interruption, which enables the vehicle to change gears and obtain neutral at a traffic light or stop sign.

If the clutch master cylinder or clutch slave cylinder fails, pressure will not be generated when the clutch pedal is pressed. When the driver tries to change gears, the pedal may stay on the floor, making it impossible to put the vehicle into gear.

To replace the clutch master cylinder, disconnect the clutch pedal from the clutch master cylinder. After accessing the clutch master cylinder—which can be very difficult—the hydraulic lines that carry the fluid to the clutch slave cylinder and the clutch master cylinder should be removed. Then, similar to the clutch fluid replacement procedure, the clutch fluid is bled. A new clutch master cylinder and hydraulic lines are installed and fresh fluid is added to the clutch fluid reservoir. Then, the clutch pedal is pressed and the pressure generated by the clutch master cylinder forces fresh fluid out to the clutch slave cylinder (which removes air from the system).

Price range for Labour of Clutch Master Cylinder Replacement: £0.00 - £0.00


Return to the top of the page
Clutch Slave Cylinder Replacement


The clutch slave cylinder is directly attached to the manual transmission casing. When the clutch pedal is pressed, pressure generated by the clutch master cylinder is applied to the clutch slave cylinder. The clutch is then disengaged.

The clutch master cylinder generates the hydraulic pressure necessary to operate the clutch assembly. The clutch assembly has two key functions: to transmit power produced by the engine to the gearbox and to disrupt that power flow when the clutch pedal is depressed.

In order for the engine to operate efficiently, a range of gears is absolutely crucial. Power produced by the engine requires the clutch assembly-enabled interruption, which enables the vehicle to change gears and obtain neutral at a traffic light or stop sign.

If the clutch master cylinder or clutch slave cylinder fails, pressure will not be generated when the clutch pedal is pressed. When the driver tries to change gears, the pedal may stay on the floor, making it impossible to put the vehicle into gear.

To replace the clutch slave cylinder, first remove the hardware that secures it to the manual transmission casing. After accessing the clutch slave cylinder—which can be very difficult—the hydraulic lines that carry the fluid to the clutch slave cylinder and the clutch master cylinder should be removed. Then, similar to the clutch fluid replacement procedure, the clutch fluid is bled. Install the new clutch slave cylinder and replace the flexible hose. Fresh fluid should be added to the clutch fluid reservoir. Then, the clutch pedal is pressed and the pressure generated by the clutch master cylinder forces fresh fluid out to the clutch slave cylinder (which removes air from the system).
About this Repair: Clutch Slave Cylinder Replacement

Recommendations:

* If the clutch function is not normal after the clutch slave cylinder has been replaced, there is likely another problem with the clutch system.

Why this happens

* The vehicle may become hard to shift if the clutch slave cylinder is failing and needs to be replaced.

* Low levels of clutch fluid or a need to top off the fluid are often signs of a problem with the clutch slave cylinder.

* The clutch fluid should be flushed until clean and clear during this replacement.

* It is often economical to replace the clutch master cylinder at the same time the slave cylinder is replaced.

Price range for Labour of Clutch Slave Cylinder Replacement: £0.00 - £0.00


Return to the top of the page
Differential Drain and Refill


The purpose of the differential is to distribute engine energy to the axles so that the axles spin the wheels the right way at the right speed. The differential also allows the wheels to spin at different rates as a vehicle rounds a corner. The inside wheel spins slower than the outside wheel when turning; this "difference" is how the differential gets its name.

The differential contains gears and bearings that are lubricated by oil. Like all oils and fluids in a vehicle, the oil in the differential should be changed every 30,000 miles or more frequently if you use your vehicle to tow or carry heavy loads.

To drain and refill the differential fluid the vehicle is driven to get the differential oil warm. The oil is then drained from the differential and refilled with fresh oil.

Price range for Labour of Differential Draining & Refilling: £0.00 - £0.00


Return to the top of the page
Drive Shaft Repair


The drive shaft on a rear-wheel or four-wheel-drive vehicle transfers power from the transmission to the differential at the rear of the vehicle.

The drive shaft must be able to rotate and move upward and downward along with the movement of the rear suspension. The flexibility for suspension movement is incorporated into the drive shaft's design. To allow "flexibility" during changes in suspension height, the drive shaft has universal joints or flexible couplings at each end of the drive shaft.

If the joints or couplings are worn, the drive shaft will need to be removed from the vehicle to replace them.

The drive shaft should be periodically inspected for damage or wear. Worn universal joints may cause a squeaking or clunking sound when the vehicle is accelerating. The driver may also experience a shuddering sensation while the vehicle is in motion. Neglecting these signs could cause the drive shaft to separate from the vehicle, making the repair more expensive and possibly damaging the vehicle.

Price range for Labour of Drive Shaft Repair: £0.00 - £0.00


Return to the top of the page
Drive Shaft Universal Joint Replacement


Sometimes referred to as Replace Universal Joints, Universal Joints Replace, Replace Drive Shaft Joints, Replace Universal Joint, Universal Joint Replace, Replace Universal, Replace Drive Shaft, Drive Shaft Replace

The drive shaft transmits power from the transmission to the differential at the rear of the vehicle. Suspension flexibility is incorporated into the drive shaft. To allow flexibility during changes in suspension height, each end of the drive shaft has a universal joint or flexible coupling.

If you hear squeaking or clunking when you accelerate, your cars universal joints may be worn. You may also feel a “shuddering” when driving. Neglecting these signs could cause the drive shaft to separate from the vehicle. At best, this is an expensive repair. Worst case: your vehicle can be damaged.

Universal joints should be inspected at every oil change. If the joints or couplings need to be replaced, the drive shaft must be removed first.

Price range for Labour of Drive Shaft Universal Joint Replacement: £0.00 - £0.00


Return to the top of the page
Automatic Transaxle


The automatic transaxle combines the vehicle's automatic transmission and differential (a device that allows each of the wheels to rotate at different speeds while supplying equal torque to each of the them) in one integrated unit. Automatic transaxles are found on all front-wheel drive and many four-wheel drive vehicles.


Return to the top of the page
Automatic Transmission


A large assembly of encased gears and hydraulic clutches riding on sy component in the clutch system, the clutch pressure plate provides the clamping force that applies and releases the clutch disc. The clutch pressure plate is attached to the engine flywheel and covers the clutch disc.


Return to the top of the page
Clutch



A Clutch usually consists of at least two discs mounted to two different turning shafts that allows the coupling or decoupling of the two shafts. The coupling/decoupling action is enabled by a squeezing mechanism that presses the two discs together for enagagement or lets them rotate independently for disengagement.



Return to the top of the page
Clutch Assembly


A Clutch Assembly is typically a friction disc that rides on the transmission input shaft and a spring loaded pressure plate that squeezes the friction disc to the flywheel to engage the engine to the transmission. When the pressure plate is released, the clutch assembly is disengeged and the friction disc and flywheel can rotate independently.



Return to the top of the page
Clutch Cable


When you press the clutch pedal, the clutch cable is pulled. The cable operates the clutch assembly, which disengages the clutch and allows you to shift gears.

Mechanics' Corner: More Technical Detail
Clutch cables must compensate for wear and/or stretching at the clutch. Clutches using cables have largely been supplanted by the more modern self-adjusting hydraulic release mechanisms.



Return to the top of the page
Clutch Disc


The clutch disc is a friction disc that connects the engine and the transmission's input shaft. The disc allows a temporary disconnection between the engine and transmission so you can shift gears. The disc is made of a similar material to brake pads, so it eventually wears out and needs to be replaced.



Return to the top of the page
Clutch Master Cylinder


The clutch master cylinder generates the hydraulic pressure necessary to operate the clutch assembly. When the driver presses down on the clutch, the clutch master cylinder uses that pressure to push hydraulic fluid through a pipe and into the clutch slave cylinder (which operates the clutch assembly). The hydraulic fluid is nothing more than conventional brake fluid.



Return to the top of the page
Clutch Pilot Bearing


The clutch pilot bearing provides a rotating link between the engine crankshaft and the transmission input shaft.

When the clutch is not fully applied, the engine crankshaft speed and the transmission input shaft speed are different. The clutch pilot bearing allows the transmission input shaft—which extends into the engine crankshaft—to rotate independently at these times.

When the clutch is fully applied, the engine crankshaft and transmission input shaft rotate as one and the clutch pilot bearing is not needed.



Return to the top of the page
Clutch Pressure Plate


A key component in the clutch system, the clutch pressure plate provides the clamping force that applies and releases the clutch disc. The clutch pressure plate is attached to the engine flywheel and covers the clutch disc.



Return to the top of the page
Clutch Release Bearing


The clutch release bearing—commonly referred to as the "throw out" bearing—enables operation of the solidly-mounted clutch release mechanism. By providing a ball bearing between the two components, the clutch release bearing depresses and releases the clutch pressure plate, which is rotating at engine speed. The clutch release bearing should be replaced as part of the clutch.


Return to the top of the page
Clutch Slave Cylinder


The clutch slave cylinder is a hydraulic part driven by the clutch master cylinder. Its primary function is to disengage the clutch when the clutch pedal is depressed. The clutch slave cylinder operates the clutch release mechanism using hydraulic fluid, which is nothing more than conventional brake fluid.


Return to the top of the page
Clutch Start Inverter (Hybrid)


The Clutch Starter Inverter is typically the smaller Electric Motor in a Hybrid Power Unit or Inverter. The Hybrid Computer can command this motor to act as a Starter Motor to start the supplemental gasoline engine or to act as a Generator and capture rotational energy from the turning wheels as the vehicle is slowing down which creates a Magnetic Braking effect. There is a dry, Centrifugal Clutch mounted to the Engine side of the small electric motor that engages the Hybrid drive train to the gasoline engine when its rotational speed goes above a specified threshold.


Return to the top of the page
Cruise Control


Cruise Control is an Electronic-Mechanical system that is designed to maintain a pre-set steady vehicle speed by applying or releasing the necessary amount of throttle to the engine based on inputs such as vehicle speed, driver acceleration/deceleration and/or braking requests.


Return to the top of the page
Differential


The purpose of a Differential is to change the direction of the torque from the transmission to the drive wheels by a 90 degree angle. It is a large T-shaped housing that contains two sets of gears. There is a Ring and Pinion gear set which function as the drive gears and there is a smaller set of "spider" or "side gears" that enable the two wheels to turn at slightly different speeds, which is necessary, whenever the vehicle is going around a curve.


Return to the top of the page
Differential Clutch Kit


A Differential Clutch Kit is a set of friction plates that lock both wheels of the Differential together during heavy acceleration. This is to prevent just one wheel from slipping, if it loses traction under acceleration, thereby allowing both of the wheels to be drive wheels. This is often referred to as a "Posi-Traction" or "Limited-Slip" type of Differential.


Return to the top of the page
Differential Oil


The differential contains gears and bearings that are lubricated by oil. Without this lubrication, friction can wear down the gears and bearings, causing them to fail.

Important Note: Requirements for differential oil are vehicle-specific. The wrong oil can damage your vehicle.


Return to the top of the page
Drive Shaft


The drive shaft on rear wheel–drive vehicles transfers power from the transmission to the differential at the rear of the vehicle. On front wheel–drive vehicles, the drive shaft or half shaft transfers power from the transaxle to the wheels.


Return to the top of the page
Gear Position Sensor


Located on the transmission, the gear position sensor (GPS) has a series of switches that communicate the gearshift position to the transmission control module. Failure of this sensor may illuminate the Check Engine Light, cause transmission shifting issues, and make it impossible to start the car. If your engine won't turn over, move the gear shifter to neutral and try again.

The gear position sensor also controls the "P - R - N - D - L" display on the instrument panel and shift lever.


Return to the top of the page
Gearbox Oil


Gear oil is made specifically for transmissions, transfer cases, and differentials. Some gearboxes use conventional engine oil, while others use a higher viscosity oil to better protect the gears. When used in a manual transmission, gearbox oil is called "manual transmission fluid".

Manual transmission fluid is typically a 75-90 weight gear oil whose purpose is to lubricate and cool the mechanisms of a manual transmission. It is capable of maintaining proper lubrication under the very high pressure created by the gears meshing and can be a conventional or fully synthetic oil. In a few cases, some manual transmissions use an automatic transmission fluid for lubricant.


Return to the top of the page
Hydraulic Clutch Assembly


A Hydraulic Clutch Assembly is typically a set of clutch plates that ride inside a shaft mounted, rotating drum and piston assembly that is immersed in hydraulic oil. The clutch plates are connected to another rotating shaft and are pressed together by hydraulically applying the piston, thereby engaging the two rotating shafts.


Return to the top of the page
Manual Transmission


A large assembly of encased gears riding on shafts whose purpose is to provide the best gear ratio that optimizes the torque output from the engine to the drive wheels. All shifting between gear ratios is manually performed by the driver. A typical manual transmission has 5-6 forward gear ratios and a reverse.


Return to the top of the page
PCM (Power Train Control Module)


The Power Train Control Module is a powerful computer that manages the Engine's Ignition, Fuel Injection, and Emission Systems. In many vehicles it controls the operation of the Transmission and Anti-Lock Brake Systems as well.


Return to the top of the page
Pilot Bearing


A Pilot Bearing is either a bronze bushing or encased ball bearing that resides in the rear hub of the crankshaft that centres and supports the front of the transmission input shaft.


Return to the top of the page
Shift Control Solenoid


A Shift Control Solenoid is a computer controlled and electronically activated magnetic valve that allows hydraulic transmission fluid to flow into or out of a transmission shift control circuit in order to engage or disengage a particular transmission gear ratio.


Return to the top of the page
Shift Fork


A Shift Fork is a forked end metal lever that straddles a manual transmission gear shaft. Its purpose is to slide gears into or out of engagement with other gears in order change from one gear ratio to another in a manual transmission.


Return to the top of the page
Synchronizers


A synchronizer is a manual transmission engagement assembly that rests between two gears and contains a set conical brass rings. When the brass rings are pressed together during a gear shift, they adjust and match the speed of the two gears, allowing them to smoothly engage. Often these are called "synchros" in conversation.


Return to the top of the page
Throttle


The Throttle is a round metal "butterfly" blade that resides inside the round 'bore' of the throttle body and controls the amount of air that is allowed to enter a gasoline engine. The opening/closing of this blade is controlled by a cable attached to the Throttle Pedal or by a computer controlled Electronic Throttle Motor.


Return to the top of the page
Throttle Body

The Throttle Body is a housing that is bolted on to the entrance of the Intake Manifold and contains the round opening or Throttle Bore that contains the round metal throttle blade that controls the amount of air that is allowed to enter a gasoline engine.


Return to the top of the page
Torque Converter

A torque converter is a fluid coupling device designed to transfer rotating power from an engine to a rotating driven load such as a transmission and is able to multiply the amount of torque being applied to the driven load with any substantial difference between the speed of the engine and the transmission input shaft.


Return to the top of the page
Transmission

A large assembly of encased gears riding on shafts whose purpose is to provide the best gear ratio that optimizes the torque output from the engine to the drive wheels. Shifting between gear ratios is performed by the driver in a manual transmission or is performed automatically in the case of an automatic transmission. Modern transmissions have from 5-7 forward gears, a Reverse and at least one Neutral.


Return to the top of the page
Transmission Cooler

A transmission cooler is a small additional radiator that cools the automatic transmission fluid. It can be a separate unit or it can be integrated into the engine radiator.


Return to the top of the page
Transmission Pump

A high capacity hydraulic pump that is typically mounted on the front of an automatic transmission. This pump provides the needed hydraulic energy or pressure to activate the mechanisms inside the automatic transmission that enable it to propel the vehicle.


Return to the top of the page
Transmission Rear Oil Seal

The transmission rear oil seal prevents transmission oil from leaking from the rear housing of the transmission.


Return to the top of the page
Universal Joint Pair

On a RWD vehicle, the drive shaft and universal joints connect the transmission to the rear differential. One end of the rotating drive shaft is coupled with the firmly-mounted transmission and the universal joints connect the other end of the rotating drive shaft to the rear differential (the part that moves up and down as the suspension moves over bumps in the road).


ELECTRICAL AND LIGHTS


Return to the top of the page
Electrical and Lights:
###### Related Services & Repairs
###### Alternator
###### Battery
###### Battery Cables
###### Battery Cable Ends
###### Door Window Motor
###### Door Window Regulator
###### Starter
###### Exterior Lights
###### - Brake
###### - Fog/Driving
###### - Headlight
###### - License Plate
###### - Side
###### - Taillight
###### - Third Brake
###### - Turn Signal

The heart of a car's electrical system are the battery and alternator. Together, they supply the vehicle with the electricity needed to power the brain of a car; the engine control unit (ECU). The electrical system also consists of critical components, including the:

* Starter
* Ignition system
* Fuel injection system
* Emissions system

And some modern luxury cars contain more than 100 individual computers. These are just a few.

* Air bag system
* Antilock brakes
* Antitheft system
* Automatic wipers
* Entertainment system
* Electronic-controlled transmission
* GPS system
* Power/heated seats
* Stability and traction control

At 12 volts, a fully charged battery stores the electricity necessary to not only power all the above components but, most important, to start the car. The battery consists of six stacked lead plates immersed in a water and sulphuric acid mixture. Explosive gases escape through the battery cover vents. Take care when charging or jump-starting batteries. “Maintenance-free” batteries replace sulphuric acid with a gel, which is safer.

A dead or dying car battery is one of the most common problems motorists face. In addition to possibly preventing the car from starting, a poorly performing battery can affect the operation of almost any vehicle system. Use only high-quality batteries, and replace your battery at the end of its useful life as part of proactive, preventive maintenance.

The alternator is a magnet rotating inside looped copper and an iron core. It produces electricity that is delivered to the battery. When the engine is running, a drive belt spins the alternator pulley. Depending on its size, an alternator can generate between 1.5 and 2.5 volts, resulting in a total electrical system output of 13.5 to 14.5 volts. A voltage regular keeps total system output below 14.5 volts to prevent overcharging and damaging the battery.

When you turn the ignition key, electrical current is sent from your battery directly to the starter, which cranks the engine’s flywheel and moves the pistons. At the same time, the battery sends electrical current to the ECU, which signals the fuel injection system to inject fuel mixed with air into the engine. The ignition system then ignites a spark to begin combustion.

Even before the car is started, electric power is sent to the fuse box, which activates accessories including lights, power windows, and the radio. Accessories that draw heavy amperage, such as aftermarket stereos and entertainment systems, can overload batteries and alternators, wearing them out twice as fast as normal.

Some newer lighting systems contain light-emitting diodes (LEDs), tiny individual lights that can burn several times longer than traditional bulbs while requiring a fraction of the electrical energy—something the battery and alternator appreciate. LEDs are also much brighter, allowing automakers to improve the quality and safety of night time driving.



Return to the top of the page
Alternator Replacement

Sometimes referred to as Alternator, Generator

The alternator charges the battery and powers the vehicle's electrical system when the engine is running. It provides electrical energy to keep the battery fully charged and to power vehicle systems in use (e.g. the starter motor, lights, and stereo).

The alternator produces an alternating current, which is changed to usable direct current by the rectifier diodes within the alternator. The voltage regulator regulates the output voltage of the alternator. On most modern vehicles, the regulator is housed inside the alternator, but it can be externally-mounted. In either case, the voltage regulator can usually be replaced apart from the alternator.

To replace the alternator, the technician must first disconnect the battery and remove the alternator drive belt. Then the alternator is removed from the engine compartment. After installing the new alternator, the technician tightens the alternator drive belt and reconnects the battery.

To prevent damage to the alternator, proper procedures must be followed when jump-starting the vehicle or when using a battery charger to charge the battery. Never disconnect the battery from the vehicle when the engine is running. The battery absorbs excess voltage from the alternator and without it, the higher voltage may destroy the vehicle's electrical and electronic components.

Important Note: Since the alternator is designed to maintain a charged battery, charging a dead battery by driving the vehicle places a strain on the alternator. Charging a dead battery requires a sustained and substantial flow of current, which is not what the alternator is designed for. Repeatedly jump-starting and then driving a vehicle to charge the battery can lead to alternator failure.

Mechanics' Corner: More Technical Detail

The alternator is an electrical-generating device with a belt-driven pulley, which is turned or driven by the engine. Once the engine is started, the alternator supplies the electrical energy the vehicle needs.

The alternator sends electrical energy back to the battery in order to keep it fully charged. When the vehicle is running, the battery stores a large reserve of electrical energy to be used during moments of peak electrical demand (like on a cold, dark, and rainy morning when the lights and heater are on, the windshield wipers are working hard, the seat warmers are on, and the electric windshield defrosters are operating). When the vehicle is stopped and the engine is idling, the alternator cannot keep up with all of this electrical load, so the electrical system will draw energy from the reserve in the battery to meet the demand. When the vehicle is moving, the engine turns the alternator much faster, therefore generating enough electricity to meet (and exceed) demand—this is when the battery is recharged.

In modern vehicles, the amount of voltage supplied by the alternator is regulated by the engine computer where previously, a voltage regulator was built in to the alternator itself. Due to the growing number of onboard computer systems and the fact that newer vehicles need to maintain an ever-tightening envelope of voltage, the voltage regulation was transferred to the more powerful and sophisticated engine (or power train) computer.

How an Alternator Works

An alternator is a device that uses a rotating iron shaft that is wound with very thin copper wires into what is called a field winding. The ends of the windings are connected to a regulated voltage source. As the vehicle needs more voltage, the electrical system provides more electrical current, which is applied to the field windings on the rotating iron core (the "rotor"). This creates a magnetic field that induces AC voltage into a surrounding set of copper windings (called the "stator" because it is stationary). The AC voltage from the stator flows through a set of one-way electrical gates called diodes. The diodes only allow DC voltage back into the electrical system by way of the B+ or battery output terminal on the back of the alternator that is directly cabled to the positive terminal on the battery.

Things to Be Aware of When Replacing the Alternator

Before replacing the alternator, always make sure that the key is out of the ignition, that all doors are closed, and all interior and exterior lights are off. Disconnect the negative battery cable first. This will shut down all the computers on the vehicle without sending a harmful electrical surge throughout the system (which can damage the sensitive electronic devices). These electronics are designed with specific polarity in mind and utilize diodes (one-way electrical gates) to protect them. Disconnect the negative (ground) side first; then disconnect the positive battery cable. During the mechanical removal of the alternator, while the alternator fasteners are removed and the drive belt is released, the electrical system releases any reserve capacitance (the electrical energy stored in the various systems and their components). When the new alternator is installed, the positive battery cable must be connected first and the negative battery cable connected last.

About this Repair: Alternator Replacement

Recommendations:

* The entire starting and charging system should be inspected before replacing the alternator to eliminate other problems that may be affecting the alternator's performance.

* We recommend replacing the alternator belt with the alternator if it does not require too much additional labour.

Why this happens:

* A weak alternator can result in unusually dim headlights.

* The battery may need to be replaced along with the alternator. If the battery does not deliver 10 volts or more in the shop's tests, the vehicle may continue to experience starting problems.

* A failing alternator can result in problems starting the vehicle, and repeated jump starts.

Price range for Labour of Alternator replacement: £0.00 - £0.00



Return to the top of the page
Battery Cable End Replacement

The battery cables and battery cable ends carry power to all the car's electrical components (starter motor, lights, stereo, etc.).

The battery cables must be secure and free from corrosion to function properly.

If battery cables are not properly secured, or if they suffer from corrosion, the vehicle may be hard to start, or may not start at all.

When replacing the battery cable or the battery cable end, apply the emergency brake, remove keys from the ignition, and turn off all electrical components. After replacing the battery cable or cable end, you'll need to reset the time clock and radio presets.

Mechanics Corner: More Technical Detail

The battery cable terminals must be kept clean and free of corrosion. If they become dirty or corroded, they will rob the vehicle of needed electrical current.

When replacing any battery terminal the cable itself must be inspected, if there is any evidence of corrosion in the cable strands the entire cable must be replaced. This is because the corrosion inside the cable will absorb critical amounts of electrical energy. This excess absorption of electrical energy in the cable can get to the point where the vehicle's starter will not turn over the engine even though the battery and starter are brand new. Corroded cables can absorb well over 50% of the electrical energy, making the actual voltage available from the battery 6 volts or less!

Price range for Labour of Battery Cable End Replacement: £0.00 - £0.00



Return to the top of the page
Battery Cable Replacement

Sometimes referred to as Negative Battery Cable, Battery Cable Negative, Negative Cable

The battery cables and battery cable ends carry power to all of a vehicle's electrical components (starter motor, lights, stereo, etc.).

The battery cables must be secure and free from corrosion to function properly.

If battery cables are not properly secured, or if they suffer from corrosion, you may have a hard time starting the vehicle, or it may not start at all.

When replacing the battery cable or the battery cable ends, you should apply the emergency brake, remove the keys from the ignition, and switch off all electrical components. After replacing the battery cable or cable end, you'll need to set the time clock and radio presets.

About this Repair: Negative Battery Cable Replacement

Recommendations:

* The entire starting and charging system should be inspected before replacing the battery cables to eliminate other problems that may be affecting the system's performance.

Why this happens:

* Battery cables may need to be replaced if the starter has recently been replaced and is still not operating optimally.

* Be sure to use a replacement battery cable that is as thick as or thicker than the original cable. The incorrect cable may be less expensive, but it may cause problems with the electrical system.

Price range for Labour of Battery Cable Replacement: £0.00 - £0.00



Return to the top of the page
Battery Replacement

Sometimes referred to as Battery

The battery, in conjunction with the alternator, supplies the electrical power needed for the lights, stereo, and all other electrical components.

Periodically check battery cables to ensure they are clean and tight; also, check the fluid level in the battery. If you have a maintenance-free battery, there is a window on top that shows the state of charge.

No battery should be replaced without proper testing (e.g. individual cell voltage, load, and conductance tests). A properly functioning charging system (including cables and wiring) is a prerequisite to battery testing. Electrical faults that cause electrical current flow—sometimes in very low amounts after the vehicle is shut off—can cause chronic dead battery problems.

When replacing the battery, battery cable, or the battery cable end, apply the emergency brake, remove the keys from the ignition, and turn off all electrical components. Before disconnecting the battery, make sure the radio anti-theft code is available; some vehicles require certain systems to be reset or "learned" after the battery is installed. These can include engine and/or transmission adaptation, power window pinch protection, power seat/mirror settings, and radio station presets.

To replace the battery, remove the hardware securing the battery, the battery cables, and the old battery. Install the new battery, reinstall the battery cables and hardware, and secure and tighten the new battery connections.

Mechanics' Corner: More Technical Detail

An automotive battery is an electro-chemical device that uses a mixture of sulphuric acid and water that surrounds lead plates in six separate areas called cells. Ideally, each cell develops 2.1 volts for a total of 12.6 volts.

When removing an automotive battery, the key should be removed from the ignition, the electrical loads turned off, and all vehicle doors closed. The negative cable is always removed first, followed by the positive cable. After removing both cables, the hardware holding brackets are removed. If you carefully follow these steps, any reserve voltage in the electrical system will equalize.

When installing the new battery, always connect the positive cable first, followed by the negative cable because the computer memory and adaptive functions will start to energize as soon as the new battery is connected. To avoid damaging the computers or software in the vehicle, it is important to have the correct polarity.

About this Repair: Battery Replacement

Recommendations:

* A high-quality battery will last for more than 4 years, but even high-quality batteries should be replaced before they become corroded or weak.

* We recommend high-quality replacement batteries because of the extensive electrical systems that are reliant on a strong battery.

* We recommend replacing batteries that are showing signs of age and heavy corrosion.

Price range for Labour of Battery Replacement: £0.00 - £0.00



Return to the top of the page
Brake Light Bulb Replacement

It is important to use a brake light bulb that meets the vehicle manufacturer's specific. Using an incorrect style or type of bulb may cause damage to the wiring or lamp housing.

You may need to remove the lamp assembly or even some trim panels to gain access to the defective brake light bulb.

Price range for Labour of Brake Light Bulb Replacement: £0.00 - £0.00



Return to the top of the page
Door Window Motor Replacement

Any vehicle equipped with electric windows has an electric motor in each door. When the driver or a passenger pushes the window-switch control panel, the window raises and lowers.

Intermittent electric window operation is often caused by a wiring problem or switch failure. The wiring harness that carries power to each door flexes each time the door is opened and closed. This motion can, over time, cause this harness to fatigue and fail.

To replace the door window motor, the inner door trim panel must be removed. Next, the door window regulator is separated from the window glass. Then the electric motor and door window regulator are removed from door, and the window-switch control panel and electric motor are separated. The electric motor is replaced, and the door components are reassembled in reverse order.

Price range for Labour of Window Motor Replacement: £0.00 - £0.00



Return to the top of the page
Door Window Regulator Replacement

The door window regulator is the mechanism that raises and lowers the door window glass on both power and manually-operated windows.

Vehicles equipped with electric windows have an electric motor in each door. When the driver/passenger pushes the window-switch control panel, the window raises and lowers. This electric motor operates a mechanical linkage called the door window regulator, which is attached to the door's window glass.

Wear in the door window regulator may cause the window to open or close improperly—or not move at all—even though the motor can be heard when the window-switch control panel is operated.

To replace the door window regulator, first remove the inner door trim panel. Then, remove the regulator from the window glass and then remove the glass itself. Separate the electric motor and door window regulator and replace the window-operating mechanism. The components are then reassembled in reverse order.

Price range for Labour of Window Regulator Replacement: £0.00 - £0.00



Return to the top of the page
Fog Light/Driving Light Bulb Replacement

Sometimes referred to as Fog Light, Fog Lights, Driving Light, Driving Lights, Replace Fog Light, Replace Fog Lights, Fog Light Replace, Fog Lights Replace, Driving Light Replace, Driving Lights Replace, Replace Driving Light, Replace Driving Lights

It is important to use a fog light or driving light bulb that meets the vehicle manufacturer's specifications. Using an incorrect style or type of bulb may cause damage to the wiring or lamp housing.

You may need to remove the lamp assembly or some trim panels to gain access to the defective fog light bulb.

It is important to use a headlamp light bulb that meets the vehicle manufacturer's specifications. Using an incorrect style or type of bulb may cause damage to the wiring or lamp housing.

You may need to remove the lamp assembly or some trim panels to gain access to the defective headlamp bulb.

Vehicles with high-intensity (HID) headlights supply high voltage to the headlight bulbs. Use extreme caution when working on or near the headlights.

Price range for Labour of Fog / Driving Light Bulb Replacement: £0.00 - £0.00



Return to the top of the pageHeadlamp Bulb Replacement


It is important to use a headlamp light bulb that meets the vehicle manufacturer's specifications. Using an incorrect style or type of bulb may cause damage to the wiring or lamp housing.

You may need to remove the lamp assembly or some trim panels to gain access to the defective headlamp bulb.

Vehicles with high-intensity (HID) headlights supply high voltage to the headlight bulbs. Use extreme caution when working on or near the headlights.




Return to the top of the page
License Plate Light Bulb Replacement

It is important to use a license plate light bulb that meets the vehicle manufacturer's specific. Using an incorrect style or type of bulb may cause damage to the wiring or lamp housing.

You may need to remove the lamp assembly or some trim panels to gain access to the defective license plate bulb.

Price range for Labour of License Plate Light Bulb Replacement: £0.00 - £0.00



Return to the top of the page
Side Light Bulb Replacement

It is important to use a side/marker light bulb that meets the vehicle manufacturer's specific. Using an incorrect style or type of bulb may cause damage to the wiring or lamp housing.

You may need to remove the lamp assembly or some trim panels to gain access to the defective side/market light bulb.

Price range for Labour of Side Light Bulb Replacement: £0.00 - £0.00



Return to the top of the page
Starter Replacement

By harnessing the power of the battery, the starter motor powers the car to "turn over," or start when the driver turns the ignition switch. The starter motor also enables the driver to restart the engine once it has been switched off.

When the starter motor causes the engine to revolve at about 350–450 rpm, the engine develops enough vacuum to enable combustion to occur, which is what causes the engine to start. Once the engine starts, the driver releases the ignition key from the start position, allowing the starter to disengage.

Price range for Labour of Starter Motor Replacement: £0.00 - £0.00



Return to the top of the page
Tail Light Bulb Replacement

It is important to use a tail light bulb that meets the vehicle manufacturer's specific. Using an incorrect style or type of bulb may cause damage to the wiring or lamp housing.

You may need to remove the lamp assembly or some trim panels to gain access to the defective tail light bulb.

Price range for Labour of Tail Light Bulb Replacement: £0.00 - £0.00



Return to the top of the page
Third Brake Light Bulb Replacement

It is important to use a third brake light bulb that meets the vehicle manufacturer's specific. Using an incorrect style or type of bulb may cause damage to the wiring or lamp housing.

You may need to remove the lamp assembly or some trim panels to gain access to the defective third brake light bulb.

Price range for Labour of Third Brake Light Bulb Replacement: £0.00 - £0.00



Return to the top of the page
Turn Signal Bulb Replacement

It is important to use a turn signal light bulb that meets the vehicle manufacturer's specific. Using an incorrect style or type of bulb may cause damage to the wiring or lamp housing.

You may need to remove the lamp assembly or some trim panels to gain access to the defective turn signal light bulb.

Price range for Labour of Turn Signal Bulb Replacement: £0.00 - £0.00



Return to the top of the page
Alternator

The alternator is an electrical generating device. It has a belt driven pulley that is turned or rotated by the engine. It is like the main pumping station in a city water supply system in that it regulates how much energy is allowed into the electrical system. During peak electrical demand, such as when the lights, heater, seat warmers, windshield wipers and rear windshield defroster are all being used on a cold, dark, rainy morning, the alternator is unable to supply all the electricity needed. When this happens, the electrical system will draw energy from the battery in order to maintain this peak in system wide electrical demand. When the electrical loads are reduced, the alternator recharges the battery back to its ideal voltage of 12.6 volts.

Note: There are time limiting circuits in the window defroster and seat warmer circuits in order to protect the battery from overload and/or becoming too discharged.

Mechanics Corner: More Technical Detail

The alternator is an electrical-generating device with a belt-driven pulley, which is turned or driven by the engine. Once the engine is started, the alternator supplies the electrical energy the vehicle needs.

The alternator sends electrical energy back to the battery in order to keep it fully charged. When the vehicle is running, the battery stores a large reserve of electrical energy to be used during moments of peak electrical demand (like on a cold, dark, and rainy morning when the lights and heater are on, the windshield wipers are working hard, the seat warmers are on, and the electric windshield defrosters are operating). When the vehicle is stopped and the engine is idling, the alternator cannot keep up with all of this electrical load, so the electrical system will draw energy from the reserve in the battery to meet the demand. When the vehicle is moving, the engine turns the alternator much faster, therefore generating enough electricity to meet (and exceed) demand—this is when the battery is recharged.

In modern vehicles, the amount of voltage supplied by the alternator is regulated by the engine computer where previously, a voltage regulator was built in to the alternator itself. Due to the growing number of onboard computer systems and the fact that newer vehicles need to maintain an ever-tightening envelope of voltage, the voltage regulation was transferred to the more powerful and sophisticated engine (or power train) computer.

How an Alternator Works:

An alternator is a device that uses a rotating iron shaft that is wound with very thin copper wires into what is called a field winding. The ends of the windings are connected to a regulated voltage source. As the vehicle needs more voltage, the electrical system provides more electrical current, which is applied to the field windings on the rotating iron core (the "rotor"). This creates a magnetic field that induces AC voltage into a surrounding set of copper windings (called the "stator" because it is stationary). The AC voltage from the stator flows through a set of one-way electrical gates called diodes. The diodes only allow DC voltage back into the electrical system by way of the B+ or battery output terminal on the back of the alternator that is directly cabled to the positive terminal on the battery.

Price range for Labour of Fixing Alternator: £0.00 - £0.00



Return to the top of the page
Alternator Belt

The alternator belt is a flexible rubber belt driven by the engine to power the alternator. The alternator belt can be the common "V" profile or the more modern flat-ribbed style.



Return to the top of the page
Alternator Discharge Light

The purpose of the Alternator Discharge Light or "Charging System Light" is to provide a Charging System self-test and to alert the driver if there is a problem in the Charging System on their vehicle. When the vehicle is first started, the Charging System Light should illuminate and then go out within 1-2 seconds. If the Light behaves in any other way, the Charging System should be inspected.



Return to the top of the page
Alternator Harness Connector

The Alternator Harness Connector is a multi-wire plastic connector that plugs into the body of the Alternator that typically connects the Charging System Light, Field Circuit and Voltage Regulator to the Instrument Cluster and Power Train Computer.



Return to the top of the page
Battery

At 12.6 volts, a fully charged battery stores and supplies the electrical energy needed to crank over and start the engine. However, once the vehicle is running it is the alternator that takes over and continues to supply the energy that operates the vehicle. The battery is much like the reservoir in a city water supply system, there is a flow in-to and out-of the battery.

Mechanics' Corner: More Technical Detail

An automotive battery is an electro-chemical device that uses a mixture of sulphuric acid and water that surrounds lead plates in six separate areas called cells. Ideally, each cell develops 2.1 volts for a total of 12.6 volts. The physical size and electrical capacity of the battery are vehicle-specific.



Return to the top of the page
Battery Cable Ends

Battery cables have large connections attached to their ends for connecting to the battery, starter, and alternator. Battery cables (the largest on the vehicle) and battery cable ends carry a tremendous amount of electrical energy.



Return to the top of the page
Battery Control Module

The purpose of the Battery Control Module is to continually calculate the state of charge for the High Voltage Battery in a Hybrid vehicle based on its Current, Voltage and Temperature. It then sends this information to the High Voltage Control Unit which then performs the proper amount of charge and/or discharge to the High Voltage Battery.



Return to the top of the page
Battery Positive Connector

The Battery Positive Connector is a separate and robust, ringed eyelet connector that connects the Battery Positive Terminal to the B+ output terminal on the back of the Alternator by way of a heavy gauge, thick and well insulated copper wire.



Return to the top of the page
Battery Post Protective Pad

Battery post protective pads are chemically treated felt rings that fight terminal corrosion.



Return to the top of the page
Brake Light Bulb

Exterior lights let drivers see the road at night and in foggy conditions. Exterior lights also signal other drivers about driving intentions and emergency situations.



Return to the top of the page
Circuit Breaker

A Circuit Breaker is a Circuit Protection device that is uses a bimetallic strip to bridge a circuit. When the current in the circuit reaches a predetermined level, the bimetallic strips heats up and bends, which disconnects the circuit and protects it from being damaged from overheating. Over time the strip will cool down, become straight and reconnect the circuit.



Return to the top of the page
Door or Truck Lock Cylinder

The purpose of the Door or Trunk Lock Cylinder is to provide a level of security that requires a coded metal Door or Trunk Lock Key in order for the outside Door/Trunk Lock to be operated which, allows entry in to the vehicle.



Return to the top of the page
Door Window Motor

Vehicles equipped with electric windows have an electric motor in each door. When the driver/passenger pushes the window-switch control panel, the window raises and lowers. Window motor assemblies have become increasingly sophisticated; assembled as a "module," they can incorporate automatic functions to raise and lower the window as well as "pinch protection" features to prevent window closure if an obstruction (i.e. a hand or finger) is sensed.



Return to the top of the page
Door Window Regulator

The regulator is a mechanism that raises and lowers the door window glass on both power and manually-operated windows. Some window regulators have a robust, all-metal "scissor" design and some utilize a travelling metal strap that raises and lowers the glass. Lightweight and economically constructed, the most common regulator today is the stranded metal cable with plastic pulleys.



Return to the top of the page
Fog/Driving Light Bulb

Exterior lights let drivers see the road at night and in foggy conditions. Exterior lights also signal other drivers about driving intentions and emergency situations.



Return to the top of the page
Fuse

A fuse is a circuit protection device that that uses a thin strip of metal to bridge a circuit that is designed to melt when a predetermined current level is reached thereby preventing the circuit from overheating and being damaged. Automotive Fuses are graded by amperage and can range from 1-2 to over 100 amps.



Return to the top of the page
Fuse Box

The Fuse Box is an Electrical Power Distribution and Circuit Protection Centre. A large Power Cable feeds current in to the Fuse Box where it divides in to several smaller Circuits that are Fused or protected. Most vehicles have an under hood and an interior fuse box.



Return to the top of the page
Fusible Link

A Fusible Link is a Circuit Protection device that uses a soft metal wire to bridge a circuit. When the current in the circuit reaches a predetermined level, the wire will melt away and disconnect the circuit, which protects it from overheating and being damaged.



Return to the top of the page
Hazard Light Bulb

Hazard lights, also known as four-way flashers, signal other drivers of emergency situations.



Return to the top of the page
Headlamp Light Bulb

Exterior lights let drivers see the road at night and in foggy conditions. Exterior lights also signal other drivers about driving intentions and emergency situations.



Return to the top of the page
Ignition Distributor

The purpose of the Ignition Distributor is to direct the high voltage spark (40,000 Volts or more) from the Ignition Coil to the individual Spark Plugs in the Cylinders. It does this with a conductor on top of a rotating shaft (a Rotor) that turns and distributes the high voltage spark impulses to individual conductors that are connected to the Cylinders by Spark Plug wires.



Return to the top of the page
Ignition Lock Cylinder

The Ignition Lock Cylinder is part of the Ignition Lock Assembly. The purpose of the Ignition Lock Cylinder is to provide a level of security that requires a coded metal Ignition Key in order for the vehicle Ignition Switch to be operated and energized, thereby allowing the vehicle to be started and operated.



Return to the top of the page
Interior Lighting System

The purpose of the Interior Lighting System is to provide illumination for the Instrument Cluster and various Control Knobs and Levers throughout the vehicle and to illuminate the Interior of the vehicle so people can safely enter or exit it and/or be able to read inside the vehicle when it is dark outside.



Return to the top of the page
License Plate Light Bulb

The license plate light illuminates the license plates so they can be seen at night.



Return to the top of the page
Light Socket

A light socket is typically a round metal receptacle into which a light bulb either threads or clicks and contains power and ground contacts that illuminate the bulb when energized.



Return to the top of the page
Negative Battery Cable

There are two very large cables that come directly off the battery. Think of these cables as the large rivers that carry the water from the reservoir into a city's water main system. The negative cable is normally black, and the positive cable is normally red.

The positive cable, normally red, divides into two very large sections.

* One section goes to the engine and under hood area. Its first stop is often the starter motor and then on to a main under hood electrical distribution centre and fuse panel. Here the electrical power is divided into several fused or protected circuits, much like the main water pipes in a city water system with their gates and valves.

* The other section of the positive battery cable goes to the interior electrical distribution centre. This is also a large, fused power distribution centre that supplies the interior or passenger compartment electrical systems.

* There is also a smaller cable that goes directly from the alternator/battery output (B+) terminal directly to the positive terminal on the battery that supplies the electricity that charges the battery.

The other very large battery cable is the negative cable, normally black. It provides the ground or return path to the battery so that all of the electrical circuits have a 'pure' ground path to the battery.

* The largest section of the negative cable goes directly to the engine. This allows a return path for the huge amounts of electrical current used by the starter motor when it cranks or 'turns over' the engine. When a vehicle is being started, more electrical energy is being used than is required to power a 4 bedroom house. This is usually more than 150-250 amps. This large amount of electrical energy must return to the battery very efficiently or the starter motor will not produce the required torque that rotates the crankshaft at the speed that is needed to 'fire' the engine.

* In many cases there are branches from the negative engine battery cable that attach to other under hood systems such as the fuel injection, ignition system, anti-lock braking system and transmission controls.

* Other smaller sections of the negative battery cable are attached to the body and frame of the vehicle. This allows for the interior and exterior lighting systems to have a clear return path to ground which is the negative terminal on the battery. It also provides a 'pure' ground path to be used by other interior electrical systems though some interior electrical systems, such as the instrument panel, use individual or 'dedicated' ground wires in order to have a 'pure' and 'noiseless' return path to the negative terminal on the battery.



Return to the top of the page
Positive Battery Cable

There are two very large cables that come directly off the battery. Think of these cables as the large rivers that carry the water from the reservoir into a city's water main system. The negative cable is normally black, and the positive cable is normally red.

The positive cable, normally red, divides into two very large sections.

* One section goes to the engine and under hood area. Its first stop is often the starter motor and then on to a main under hood electrical distribution centre and fuse panel. Here the electrical power is divided into several fused or protected circuits, much like the main water pipes in a city water system with their gates and valves.

* The other section of the positive battery cable goes to the interior electrical distribution centre. This is also a large, fused power distribution centre that supplies the interior or passenger compartment electrical systems.

* There is also a smaller cable that goes directly from the alternator/battery output (B+) terminal directly to the positive terminal on the battery that supplies the electricity that charges the battery.

The other very large battery cable is the negative cable, normally black. It provides the ground or return path to the battery so that all of the electrical circuits have a 'pure' ground path to the battery.

* The largest section of the negative cable goes directly to the engine. This allows a return path for the huge amounts of electrical current used by the starter motor when it cranks or 'turns over' the engine. When a vehicle is being started, more electrical energy is being used than is required to power a 4 bedroom house. This is usually more than 150-250 amps. This large amount of electrical energy must return to the battery very efficiently or the starter motor will not produce the required torque that rotates the crankshaft at the speed that is needed to 'fire' the engine.

* In many cases there are branches from the negative engine battery cable that attach to other under hood systems such as the fuel injection, ignition system, anti-lock braking system and transmission controls.

* Other smaller sections of the negative battery cable are attached to the body and frame of the vehicle. This allows for the interior and exterior lighting systems to have a clear return path to ground which is the negative terminal on the battery. It also provides a 'pure' ground path to be used by other interior electrical systems though some interior electrical systems, such as the instrument panel, use individual or 'dedicated' ground wires in order to have a 'pure' and 'noiseless' return path to the negative terminal on the battery.



Return to the top of the page
Power Seats

Power Seats have two or more electrical motors with gear sets that power assist the adjustment of the seat. Some Power Seats have eight or more possible directions in which the seat can be adjusted and have a memory feature that will recall different seat positions with a push of one button.



Return to the top of the page
Side Lamp Light Bulb

Exterior lights let drivers see the road at night and in foggy conditions. Exterior lights also signal other drivers about driving intentions and emergency situations.



Return to the top of the page
Starter

By harnessing the power of the battery, the starter motor powers the car to "turn over," or start.

The starter motor is the heart of the starting system. It is a very powerful DC electric motor with a gear system that connects to the flywheel on the engine. The starter motor causes the engine to revolve at about 350–450 rpm and the engine develops enough vacuum to enable combustion to occur, which is what causes the engine to start. Once the engine starts, the driver releases the ignition key from the start position, allowing the starter to disengage.

The two very large battery cables are connected directly to the starter motor. The positive cable connects to the motor feed while the negative cable connects near the starter motor case.

The ignition switch provides a trigger signal when the key is turned to the start position. This trigger signal is sent to a heavy duty switching device on the starter motor called the starter solenoid. The trigger signal from the ignition switch energizes a magnetic field that brings together two large copper discs that allow the battery to feed current into the armature of the starter motor, causing it to rotate or 'crank' the engine. There is a specialized gear engagement mechanism on the end of the starter motor's armature shaft called the starter drive. When the starter motor spins, it extends a gear that engages the flywheel so the starter motor is able to rotate the crankshaft.

When the engine 'fires' it spins the starter motor gear, this gear has a special releasing mechanism called an over-running clutch. The over-running clutch allows the starter gear to spin freely on its shaft while the engine picks up speed as it begins to run. Otherwise the engine could destroy the starter motor and drive by turning it too violently and too fast. When the driver of the vehicle releases the ignition key, the trigger signal is interrupted to the magnetic field in the starter solenoid and halts the operation of the starter motor.



Return to the top of the page
Starter Relay

The Starter Relay is a device that utilizes a small amount of electrical current from the ignition switch to energize an electro magnet that operates a larger current carrying switch, which in turn triggers the operation of the Starter Motor or Starter Solenoid.



Return to the top of the page
Starter Solenoid

The Starter Solenoid is a very large relay that is commonly mounted on the Starter Motor which utilizes the small electrical "trigger" or "start" signal from the ignition switch to magnetically close two very large electrical contact disks that provide direct battery power to the Starter Motor which cranks the engine.



Return to the top of the page
Switches

A Switch is a device that closes (allows power to flow) or opens (prevents power from flowing) any electrical circuit. This is achieved by mechanically touching (closing) or separating (opening) two or more electrically conductive surfaces that connect to the respective ends or "poles" of the circuit.

Switches are used in any number of electrical components and systems in automobiles.



Return to the top of the page
Tail Light Bulb

Exterior lights let drivers see the road at night and in foggy conditions. Exterior lights also signal other drivers about driving intentions and emergency situations.



Return to the top of the page
Temperature Gauge

A temperature gauge is a device that typically indicates the engine coolant or oil temperature. It can either be an analogue gauge that uses a needle to sweep a scale that ranges from cold to hot or it can be a digital gauge that displays numerical degrees in Celsius or Fahrenheit.



Return to the top of the page
Third Brake Light Bulb

Exterior lights let drivers see the road at night and in foggy conditions. Exterior lights also signal other drivers about driving intentions and emergency situations.



Return to the top of the page
Turn Signal Light Bulb

Sometimes referred to as Turn Signal, Turn Signal Bulb, Replace Turn Signal Bulb, Turn Signal Bulb Replace, Replace Turn Signal, Turn Signal Replace, Replace Signal, Signal Replace, Replace Signal Bulb, Signal Bulb Replace, Blinker, Replace Blinker, Blinker Replace, Blinker Bulb, Replace Blinker Bulb, Blinker Bulb Replace

The turn signal light alerts other drivers about driving intentions.



Return to the top of the page
Voltage Regulator

A voltage regulator is an electronic device that senses system voltage and then adjusts the amount of charging system output in order to maintain the ideal amount of system voltage as the system loads and requirements change during different phases of operation.


ENGINE



Return to the top of the page
Cooling System

The cooling system helps regulate the amount of heat in the engine.

Your car’s engine runs most efficiently at a relatively high and steady temperature. If it’s too hot, the engine can overheat. If it’s too cold, the engine emits more pollutants, and components prematurely wear out. If the cooling system fails to keep the engine at the right temperature, it can suffer significant damage and in some cases, fail entirely.

* Related Services & Repairs
* Coolant Expansion Tank
* Cooling Fan Motor
* Cooling Fan Assembly
* Heater Blower Motor
* Heater Core
* Radiator
* Radiator hose - lower
* Radiator hose - upper
* Thermostat
* Water Pump

Although a few cars are air-cooled, most modern vehicles use liquid cooling. Here are the critical components in liquid-cooled systems.

* Coolant, or antifreeze, performs two critical function: keeping radiator fluid from freezing in wintry conditions and keeping the engine from overheating in the summer. Coolant is composed of 50 percent ethylene glycol and 50 percent water, which helps raise its boiling point and lower its freezing point. Corrosion inhibitors protect vital metallic cooling system components from corroding, and silicates lubricate seals. There are different kinds of antifreeze, which are most easily identified by their colour. How do they differ?

* "The green stuff” is the traditional coolant, which can be used in most cars. It contains lubricating silicates and corrosion inhibitors, but these silicates deteriorate rather quickly, requiring coolant changes every 2 years or 24,000 miles.

* Coolant can also be red, yellow, orange, or even purple. Most coolants not green in colour are similar: they are simply dyed different colours. They have a longer claimed service life, thus requiring fewer fluid changes—in some cases up to 100,000 miles. Refer to your owner’s manual for details on your car’s coolant requirements.

* The radiator is a heat exchanger with hundreds of individual tubes and fins that reduce the temperature of the coolant. As coolant travels through the engine passageways, it absorbs and removes heat from the engine, transporting it to the radiator. Air flows through the coolant passages as the car moves, cooling the tubes and fins, and coolant re-enters the engine with a reduced temperature.

* Radiator cap. If you’ve ever worked on a car, then you know not to remove the radiator cap while the engine is warm. That's because the cap is a pressure-release valve. It also keeps the cooling system under pressure to increase the boiling point of coolant.

* The engine, or radiator, fan can be driven by a drive belt or an electric motor. It helps cool a car when it is stationary or moving slowly.

* The thermostat helps the engine reach operating temperature by preventing coolant from circulating to the radiator, thus allowing the engine to heat up more quickly. As the engine reaches operating temperature, the thermostat opens and allows coolant to flow through the radiator.

* The water pump circulates coolant through the system via an impeller (a rotor that spins to move fluid) that is driven by a belt.

* The heater core is a smaller version of the radiator located underneath the dashboard. A motor blows air past the heater core, which transfers heat to the air. This keeps cabin occupants warm even in winter.

* Transmission cooler. In addition to keeping the engine cool, on cars with an automatic transmission the radiator is equipped with a separate heat exchanger to keep transmission fluid from boiling over.

If your car is leaking coolant, immediately determine from where and how much. If it continues to leak, schedule your car for service as soon as possible.

Price range for Labour of Fixing Cooling System: £0.00 - £0.00



Return to the top of the page
Engine

In its basic form, a combustion engine is a rather crude way of generating energy. It’s essentially a bunch of explosions happening inside a hollowed-out piece of iron. But take a closer look, and you’ll quickly learn how refined an engine really is.

Return to the top of the page
* Related Services & Repairs
Return to the top of the page
* Drive Belt/Fan Belt
Return to the top of the page
* Engine Oil
Return to the top of the page
* Engine Oil and Filter
Return to the top of the page
* Engine Oil Pressure Switch
Return to the top of the page
* Fuel Filter
Return to the top of the page
* Fuel Injector
Return to the top of the page
* Fuel Pump
Return to the top of the page
* Head Gasket
Return to the top of the page
* Ignition Cap and Rotor
Return to the top of the page
* Ignition Coil
Return to the top of the page
* Ignition Switch
Return to the top of the page
* Ignition Wire Set
Return to the top of the page
* Mass Airflow Sensor
Return to the top of the page
* Oil Pump
Return to the top of the page
* PCV Valve
Return to the top of the page
* Spark Plugs
Return to the top of the page
* Timing Belt
Return to the top of the page
* Timing Chains
Return to the top of the page
* Valve Clearance
Return to the top of the page
* Valve Cover Gasket

An engine makes 4 complete strokes for each complete engine cycle. Nearly all modern engines are four-stroke engines. Four-stroke refers to how many times a piston must travel up and down inside a cylinder to complete a full engine cycle. The engine draws in precise, micron-measured amounts of fuel and air through valves, compresses them, combusts them, and releases them. These 4 strokes are commonly referred to as suck, squeeze, bang, and blow.

* Intake Stroke. The intake valve opens, and the piston moves downward to suck in air while the fuel injector introduces fuel.

* Compression Stroke. The intake valve closes, and the piston travels upward to squeeze the fuel and air mixture.

* Combustion Stroke. The spark plug fires, creating an explosive bang in the chamber. This drives the piston down, releasing the energy required to move the automobile.

* Exhaust Stroke. The exhaust valve opens, and the piston travels upward to blow the burned fuel and air mixture out of the cylinder, through the exhaust manifold, catalytic converter, and muffler, and out the tailpipe.

The pistons in the engine all work in sync to provide ongoing rotational force. Each piston is attached to the crankshaft, which is attached to the drive train that moves the vehicle. Depending on how many cylinders the engine has, the firing order of the cylinders varies.

The valves, which regulate the intake and release of air, fuel, and exhaust, also operate in sync. They are controlled by a camshaft, which is attached to the crankshaft by a timing chain or timing belt for proper piston and valve positioning. This is critical, because without a timing chain or belt, valves and pistons can’t operate properly and can potentially collide with each other, causing serious engine damage.



Return to the top of the page
Primary Ignition System

The purpose of the Ignition System is to create a high voltage electrical spark, much like a bolt of lightning, directed into the individual cylinders to ignite or burn the highly compressed air and fuel mixture inside the individual cylinders. As this air and fuel mixture burns, it creates a rapidly expanding fuel that pushes against the top of the piston and provides rotational force called torque to the crankshaft.

The voltage can vary from 5,000 to 8,000 volts direct current (DC) per cylinder when the engine is idling, to over 40,000 volts per cylinder when the engine is working hard during acceleration. Many modern ignition systems are capable of 80,000 to 100,000 volts DC during periods of absolute peak output such as when a vehicle operator 'floors' the accelerator on a cold engine in cold weather.

There are two basic types of ignition systems.

* The Distributed Ignition System uses a single, centralized ignition coil.

* The Direct Ignition System uses several very powerful ignition coils, sometimes one per cylinder. This allows for more precise control over each individual cylinder firing. Each cylinder's firing can be finely tuned and timed in the actual firing order in real time while the engine operates. It creates a more powerful and responsive engine that burns cleaner.

Regardless of the type of ignition system utilized, the system is divided into two sections, the primary ignition system and the secondary ignition system.

The Primary Ignition System actually begins with the battery. When a vehicle is first started, it needs the 12 volts from the battery to begin the process of creating the spark that will eventually fire or 'ignite' the cylinders. The battery voltage is directed to the ignition coil by the operation of the ignition switch. Once the engine fires, the vehicle's charging system takes over and provides the electrical energy needed to sustain the operation of the ignition system.

Components of the Primary Ignition System are;

* Ignition coil
* Ignition switch
* Ignition module
* Crankshaft sensor
* Camshaft sensor

Mechanics Corner: More Technical Detail

Noise suppression is an important part of the primary ignition system. The ignition system produces radio frequency interference that, left unchecked, would cause so much buzzing in the audio speakers it would be impossible to listen to music inside a vehicle. To remedy this, noise suppression diodes, of various designs, are wired into the circuitry of the ignition system. These diodes electrically 'shock absorb' all the on-off switching and accompanying voltage spikes that are done by the ignition module to the ignition coil. These diodes also protect the sensitive semi-conductor circuits in the ignition module.

The operation of the alternator in the charging system produces an alternating current (AC) signal that can be transferred to the ignition system and will create a buzz in the audio speakers. To remedy this, there are additional diodes in the charging system that isolate it from the ignition system for the same purpose of voltage surge protection and noise suppression.

Price range for Labour of Fixing Primary Ignition System: £0.00 - £0.00



Return to the top of the page
Secondary Ignition System

The ignition system is divided in to two sections, the primary ignition system and the secondary ignition system. The secondary ignition system originates inside the ignition coil with the secondary coil windings. The secondary ignition system creates and delivers the high voltage needed to bridge the spark plug gap and ignite the compressed air to fuel mixture inside the individual cylinders. This high voltage is created inside the secondary windings of the ignition coil. The purpose of the spark is to mimic a small, tightly controlled, flame source that initializes a predictable flame front that burns across the top of the piston, thereby creating a rapidly expanding gas that pushes down on the top of the piston.

The ignition coil secondary windings absorb and transform the electrical energy that has been stored or 'waiting' inside the ignition coil primary windings. When the electricity 'jumps' from the primary windings it is transformed from a 12-volt system voltage to a very high voltage spark that can be as high as 80,000 volts direct current (DC). This high voltage, high pressure (voltage is electrical pressure) condition is urgently seeking a path to ground so it travels out of the ignition coil high voltage, secondary terminal that looks somewhat like the connectors on top of the large transformers inside power stations.

On distributed ignition systems a separate ignition coil wire connects the output of the ignition coil to the coil terminal of the distributor. The distributor is a component that distributes the coil spark to each individual cylinder by turning device called an ignition rotor in the distributor cap. The distributor cap, sometimes referred to as the ignition cap, is usually a round device that looks somewhat like a hat or 'cap'. The cap has a centre coil terminal surrounded by individual cylinder terminals that connect to each spark plug by way of dedicated spark plug wires.

The ignition rotor is mounted on a rotating shaft inside the distributor and usually connects to the camshaft via a gear mechanism. As the camshaft rotates it turns the ignition rotor whose centre touches the coil terminal. The rotating outer end of the ignition rotor passes very closely by each individual distributor cylinder terminal in the engine's firing order. When the rotor is pointing its outer end to an individual cylinder, the coil is 'fired' by the ignition module. This sends a high voltage spark out of the distributor and in to the spark plug wire that ultimately 'fires' the spark plug.

There is an individual spark plug wire for each cylinder. This is a high tension, and high voltage capable, rubber insulated cable that has a carbon core embedded in nylon. It is not like a typical electrical wire or cable that has a copper core. The carbon core can withstand the constant firing of the high voltage needed to energize the spark plugs without overheating or melting.

Price range for Labour of Fixing Secondary Ignition System: £0.00 - £0.00



Return to the top of the page
Coolant Expansion Tank Replacement

As the engine heats up, coolant expands. The coolant expansion tank provides additional storage for the expanded coolant and is the reservoir where the driver tops off or adds coolant to the engine. The tank is normally clear in colour so the driver can see the coolant level. On some vehicles, the driver may have to remove a cap to visually check the coolant level.

The expansion tank should be checked every other time the gas tank is filled. If the coolant level in the expansion tank consistently drops after topping off, there is probably a leak. A cooling system leak may be caused by a defective radiator, radiator cap, expansion tank, hose, or hose clamp.

The engine must be cool to replace the coolant expansion tank. The coolant is removed from the tank, as are the hoses going to the it. The old tank is removed from the vehicle, the new tank is installed, hoses are reinstalled, and the tank is refilled to its proper level.

The coolant expansion tank rarely needs to be replaced unless failure is common problem on that particular vehicle model.

Price range for Labour of Coolant Expansion Tank Replacement: £0.00 - £0.00



Return to the top of the page
Cooling Fan Motor Replacement

The fan lowers the temperature of the engine. The cooling fan motor is an electric motor that turns the fan blades. When the vehicle is in traffic or under heavy load, the engine relies on the fan to cool itself.

Some vehicles may use multiple electric fans for better control of the cooling system. For the most part, electric cooling fans are controlled by the same computer that controls the engine. However, in some engines, the fans are turned on and off by a temperature-sensitive switch mounted in either the radiator or elsewhere in the cooling system.

The electric cooling fan is mounted on the radiator. Failure of the fan motor usually causes overheating. A fan that runs constantly can cause poor fuel economy, unwanted noise, and may run the battery out.

The cooling fan motor is operated by a switch located in the radiator or engine's cooling passages. The electric cooling fan turns on when the engine's coolant temperature reaches approximately 195 to 210 degrees Fahrenheit.

The cooling fan assembly is attached to the radiator. To replace the cooling fan motor, the cooling fan assembly must be removed. The fan blades are separated from the defective cooling fan motor and attached to the new motor. The assembly is then re-attached to the radiator.
About this Repair: Radiator Fan Motor Replacement

What to watch out for:

* Radiator cooling fan motors are often replaced when the root cause is a failed fan motor module.

* Cooling fan motors can be overworked and damaged by a malfunctioning cooling system. If the underlying problem is not corrected, a new fan motor will be damaged before long.

Recommendations:

* The entire cooling system should be inspected and tested when the cooling fan motor is replaced.

Why this happens:

* Fluid leaks can ruin cooling fan motors; leaks should be fixed immediately to avoid recurring problems and damage.

Price range for Labour of Cooling Fan Motor Replacement: £0.00 - £0.00



Return to the top of the page
Distributor Cap and Rotor Replacement

When the engine is running, high voltage created by the ignition coil travels to the ignition cap through the coil wire to the ignition rotor. As the ignition rotor turns in the distributor, the rotor distributes the spark by sending it in a synchronized order through the spark plug wires to the spark plug located in each of the engine's cylinders.

The distributor is a main component of the ignition system. It takes very high voltage and delivers it at exactly the right time to fire the spark plugs.

Depending on the type of system, the spark created by the ignition system ranges from 12,000 to 45,000 volts. This high voltage means it’s critical that ignition system components are well insulated. If insulation breaks down, the spark never arrives at the spark plug, causing the engine to run poorly—or not at all.

To replace the ignition cap and rotor, also known as the distributor cap and rotor, the ignition wires are removed, along with the hardware securing the ignition cap to the distributor. When the cap is removed, the ignition rotor and distributor are inspected for wear. If needed, new parts are installed. Finally, the new cap is secured to the distributor and the ignition wires are reinstalled.

Having the cap and rotor inspected and/or replaced every 30,000 miles is a good way to avoid engine drivability problems.

Price range for Labour of Distributor cap & Rotor Replacement: £0.00 - £0.00



Return to the top of the page
Engine Cooling Fan Assembly Replacement

Fan blades lower the temperature of the engine. The cooling fan motor is an electric motor that turns the fan blades. When the vehicle is in traffic or under heavy load, the engine relies on the fan to cool itself.

When a vehicle is travelling fast, rushing air flows through the radiator and cools the engine. When a vehicle is in stop-and-go traffic or stuck at a traffic light, air needs to be pushed through the radiator. The engine’s cooling fan does this.

The cooling fan motor is operated by a switch located in the radiator or engine's cooling passages. The electric cooling fan turns on when the engine's coolant temperature reaches approximately 195 to 210 degrees Fahrenheit.

The cooling fan assembly is attached to the radiator. To replace the assembly, it is detached from the radiator, and a new one is installed. The engine is started and run to verify correct cooling fan operation.

Price range for Labour of Engine Cooling Fan Replacement: £0.00 - £0.00



Return to the top of the page
Engine Oil and Filter Change

Engine oil lubricates and removes heat from internal engine components. The oil filter removes harmful deposits from the engine oil, preventing them from being circulated throughout the engine.

Manufacturers differ in their recommended guidelines for when engine oil and oil filters should be changed. As a general rule, however, engine oil should be changed every 3,000 miles to keep the engine healthy and to prolong its life.

When changing or adding engine oil, follow the manufacturer's recommendation for the weight (0/30W, 5/30W, 20/50W), grade, and type of oil to use. Using an incorrect type or weight may invalidate your manufacturer's warranty.

To change the oil and filter, the technician removes the drain plug at the bottom of the engine oil pan and drains the oil. S/He removes the oil filter and replaces it with a new one. The technician reinstalls the drain plug and fills the engine with fresh oil. S/He starts the engine and checks for leaks. Finally, the technician switches off the engine, rechecks the oil level, and resets the maintenance light.
About this Repair: Oil and Filter Change

Recommendations:

* Replacing the engine oil every 3,000 to 4,000 miles, even if the manufacturer recommends it less frequently, will greatly extend the useful life of the engine.

* We recommend using a high-quality engine oil filter. Cheap filters wear more quickly and may not properly keep contaminants out of the engine.

* We recommend always replacing the drain plug gasket along with the oil and oil filter.

Why this happens:

* Using high-quality, fully synthetic oil can dramatically extend the life of the engine.

Price range for Labour of Oil & Filter Change: £0.00 - £0.00



Return to the top of the page
Engine Oil Change

Engine oil provides lubrication for—and conducts heat away from—internal engine components.

Manufacturers differ in their recommended guidelines for oil and oil filter changes. As a general rule though, engine oil should be changed every 3,000 miles to keep the engine healthy and to prolong its life.

When changing or adding engine oil, follow the manufacturer's recommendation for the weight (0/30W, 5/30W, 20/50W), grade, and type of oil to use. Using the incorrect type or weight may invalidate your manufacturer's warranty.

To change the oil, the technician removes the drain plug at the bottom of the engine oil pan and drains the oil. Then, the drain plug is inserted and the engine is filled with fresh oil. The engine is started and checked for leaks. Finally, the engine is switched off, the oil level rechecked, and the maintenance light reset.

Mechanics' Corner: More Technical Detail

Most manufacturers have now included panels that are attached to the vehicle's underside; they offer a measure of protection from debris and a means of controlling air flow to the engine and around the vehicle. These panels often completely cover the engine/transmission from below, blocking all access. Removal of one (or more) of these panels and their correct re-installation adds two new steps to the process of an oil change.

Price range for Labour of Engine Oil Change: £0.00 - £0.00



Return to the top of the page
Engine Oil Pressure Switch Replacement

When engine oil pressure drops below 3 to 6 pounds per square inch (psi), the engine oil pressure switch illuminates a light on the dashboard to tell the driver that the oil pressure in the engine is below that needed to prevent serious internal engine damage.

An engine generally produces 7 to 12 psi when idling and a maximum of 70 to 80 psi when it is being driven.

Many people assume that if the oil light doesn't come on while driving, the engine must have a sufficient amount of oil in it. However, the oil light is a low pressure warning, not an oil level indicator. If the oil light is on while the engine is running, the oil level may very well be low, but it is actually a sign that damage is occurring in the engine.

If the oil pressure switch is defective, the technician must remove the electrical connection from the switch. The technician must then unscrew the switch from the side of the engine and replace it with a new unit.

Price range for Labour of Engine Oil Pressure Switch Replacement: £0.00 - £0.00



Return to the top of the page
Fan/Drive Belt Replacement

The engine drives fan/drive belts to power components such as the alternator, AC compressor, power steering pump, and engine cooling fans.

Drive belts are made of rubber and wear out over time, especially if they come into contact with oil.

Periodic inspection is necessary to determine if drive belts need to be replaced; many manufacturers have set specific replacement intervals. If one drive belt is worn or has failed, the remaining drive belts should also be replaced. Often, drive belts are overlooked until they fail; inspection and maintenance can prevent roadside breakdowns.

Drive belts rotate when the engine is running. Follow safety precautions to avoid personal injury.

To replace the drive belts, loosen the hardware securing engine-mounted accessories, adjusting brackets, and tensioners. Remove the old drive belts and install and adjust the new drive belts.

Price range for Labour of Fan & Drive Belt Replacement: £0.00 - £0.00



Return to the top of the page
Fuel Filter Replacement

The fuel filter removes dirt and debris from the fuel system, preventing damage to the fuel pump, fuel injectors, and the fuel pressure regulator.

Many manufacturers don't specify a replacement interval, but it's wise to replace the fuel filter every 30,000 miles.

If low-quality fuel has been used or if there have been any drivability problems related to a loss of power, the fuel filter should be replaced.

Usually, the fuel filter is located under the vehicle near the gas tank or in the engine compartment. To replace the fuel filter, the engine must be off and cool. The lines to the filter are opened so gas can drain out of the old filter. Then, a new filter is installed and the engine is "turned over" until air is removed from the fuel lines.

Mechanics' Corner: More Technical Detail

Many vehicles also use a screen- or "sock"-type filter in the fuel tank. Any restriction at this or the main fuel filter location can cause performance issues such as poor performance when climbing hills or under acceleration. Blocked fuel filters can cause engine moaning noises. Due to extended replacement intervals, fuel filters tend to be overlooked during diagnostic procedures.
About this Repair: Fuel Filter Change

Recommendations:

* We recommend using high-quality fuel filters to keep contaminants out of the fuel system.

Why this happens:

* A worn fuel filter can result in a fuel system trouble code and a dashboard warning light.

* Infrequent fuel filter changes can lead to potentially expensive problems with fuel injectors.

* A dirty fuel filter can cause a "noisy" fuel pump and a loss of engine power.

* When replacing the fuel filter, the shop should also replace washers to prevent leaks in the fuel system.

Price range for Labour of Fuel Filter Replacement: £0.00 - £0.00



Return to the top of the page
Fuel Injector Replacement

The fuel injector "injects" gas under pressure into the intake manifold. The engine then sucks the gas in, and it is ignited. The ensuing explosion is part of the process the engine uses to create power.

For an engine to operate, it needs gas (fuel) to burn. This burning gas is converted into energy.

Based on calculations made by the on-board fuel injection control computer, the fuel injector injects a precise amount of gas into the engine. The computer analyzes the outside air temperature, the amount of air being drawn into the engine, the temperature of the engine, and many other parameters before deciding exactly how much gas to inject into the engine.

Water and dirt are very harmful to a fuel injector. It is important to change the fuel filter periodically. Adding fuel injection cleaner to the gas tank when refuelling may prevent fuel injectors from becoming clogged, which adversely affects drivability and fuel economy, as well as the vehicle's pollution output.

To replace a fuel injector, the fuel line to the injector is removed to relieve fuel pressure. On some vehicles, each injector can be removed from the engine separately. On others, the injectors share a common gas supply, meaning the technician must remove several fuel injectors at the same time to gain access to one specific injector. Any time an injector is removed or replaced, all fuel injector seals are replaced to eliminate the risk of fuel leaks that could cause a fire.
About this Repair: Fuel Injector Replacement

Recommendations:

* Fuel injectors need to be replaced if they are leaking fuel.

* Using lower quality gasoline can result in recurring fuel injector problems, even after a fuel injector replacement.

* It may be economical to replace all of the fuel injectors, even if not every injector has failed.

* Fuel injector seals should always be replaced along with fuel injectors.

Why this happens:

* Failing fuel injectors will cause a fuel trouble code and turn on a dashboard warning light.

Price range for Labour of Fuel Injector Replacement: £0.00 - £0.00



Return to the top of the page
Fuel Pump Replacement

The fuel pump creates pressure in the fuel lines, which pushes gasoline through the fuel injectors and into the engine.

Good gas atomization ensures maximum power. To ensure good atomization of the gas, it is injected into the engine under high pressure. The fuel pump creates and delivers pressurized gas to the fuel injectors.

The fuel pump is located either in the fuel tank itself or under the vehicle near the fuel tank. If the fuel pump is in the fuel tank, there may be a removable cover under the rear seats or trunk floor that allows access to the fuel pump. On many vehicles, if the fuel pump is in the fuel tank, the tank must be removed from the vehicle to replace the pump.

Gasoline is highly flammable. When replacing the fuel pump, the battery must be disconnected from the vehicle and proper safety procedures followed to avoid fire and personal injury.

Mechanics' Corner: More Technical Detail

When considering fuel pump/fuel supply issues, remember that both fuel pressure and volume must be correct.
About this Repair: Fuel Pump Replacement

What to watch out for:

* A clogged fuel filter or problems with the electrical system powering the fuel pump can result in symptoms similar to a failed fuel pump. Have the shop verify that the pump is the problem.

Recommendations:

* The fuel filter should always be replaced with the fuel pump.

Why this happens:

* A failing fuel pump will not create enough pressure in the fuel system, potentially resulting in a loss of engine power.

* Fuel pumps require replacement if they leak or begin making too much noise, which is a sign of malfunction.

Price range for Labour of Fuel Pump Replacement: £0.00 - £0.00



Return to the top of the page
Head Gasket Replacement

The head gasket is located between the engine's cylinder head and block. When a spark ignites gasoline in the engine, the explosion creates pressure in the engine. The head gasket provides a seal that keeps that pressure contained within the engine's cylinder. The head gasket also provides a seal for internal engine water and oil passages.

If the engine is allowed to overheat, the cylinder head gasket may become damaged. Running the vehicle when its coolant is low or when there has been a cooling system failure can cause overheating.

Replacing the head gasket requires major engine dismantling. The cooling system is drained, and the intake and exhaust manifolds are removed. The timing cover, timing belt (or timing chain), and valve covers may also need to be removed. In order to gain access to the bolts and hardware securing the cylinder head to the engine block, the camshafts may need to be removed.

After the cylinder head is removed, the cylinder head and engine block surfaces are cleaned and examined for damage. The head gasket is replaced and engine components reassembled.

Mechanics' Corner: More Technical Detail

Head gasket failure caused by severe or repeated engine overheating will necessitate close inspection of the cylinder head itself for cracks, as well as measurements taken to assure that the cylinder head is not warped. A warped cylinder head can often be machined flat, but it may have to be replaced.

Due to the damaging effects of coolant entering the combustion chamber, oxygen sensor and/or catalytic converter replacement may be prudent or even necessary. This is especially true if head gasket failure was severe or prolonged.
About this Repair: Head Gasket(s) Replacement

Recommendations:

* To prevent an expensive, recurring problem, the integrity of the entire cooling system should be inspected and tested when a head gasket is replaced.

Why this happens:

* Failed head gaskets can cause the vehicle to produce a white, sweet-smelling smoke.

* If the head gasket needs replacement, the engine is likely to be leaking oil, coolant, or both.

Price range for Labour of Head Gasket Replacement: £0.00 - £0.00



Return to the top of the page
Ignition Coil Replacement

The ignition coil generates the "spark" required to ignite gasoline. The ensuing explosion is part of the process the engine uses to create power. Older vehicles use only 1 ignition coil and a distributor to distribute the spark to each cylinder in the engine. Most modern vehicles use one ignition coil per engine cylinder. The ignition coils on these vehicles are located directly on top of the spark plug.

To replace the ignition coil, the electrical connection to the coil is disconnected and the hardware securing the ignition coil to the valve cover or manifold is removed. On some vehicles, it may be necessary to remove the intake manifold to gain access to the ignition coils.
About this Repair: Ignition Coil Replacement

Why this happens

* A failed ignition coil is commonly the result of failures elsewhere in the ignition system. The ignition wires and spark plugs should be inspected and replaced if necessary.

* Oil or coolant leaks can damage ignition coils, and the leaks need to be repaired along with the ignition coil.

* Failing ignition coils can result in an engine trouble code and a dashboard warning light.

* Failing ignition coils can cause the engine to run roughly or to lack power when accelerating.

* Corroded ignition coils require replacement.

Price range for Labour of Ignition Coil Replacement: £0.00 - £0.00



Return to the top of the page
Ignition Switch Electrical Portion Replacement

The electrical portion of the ignition switch assembly provides power to electrical components such as the stereo, windshield wipers, and electric windows. The ignition switch also supplies power to the starter motor, which enables the engine to start.

A problem with the ignition switch may make it impossible to start the engine, continuously or intermittently.

To replace the electrical portion of the ignition switch assembly, the technician must remove the trim panels around the ignition switch and disassemble the steering column. S/He then removes the electrical portion of the switch assembly and replaces it with the new component. Finally, the technician reassembles the steering column components and replaces the trim panels.

Some manufacturers supply just the electrical portion of the ignition switch (separate from the entire assembly), so the entire ignition switch assembly doesn't have to be replaced if only the electrical portion has failed.
About this Repair: Ignition Switch (Electrical Portion)

Why this happens:

* A failing ignition switch can cause a vehicle to be difficult to start or for the engine to die while driving.

* A failed electrical ignition switch can result in the engine continuing to run even after the key has been removed from the ignition.

Price range for Labour of Ignition Switch Electrical Replacement: £0.00 - £0.00



Return to the top of the page
Ignition Switch Lock Cylinder Replacement

The ignition lock assembly contains two components: a lock cylinder to deter theft and an electrical portion that supplies power to electrical components such as the radio, electric windows, and windshield wipers. The electrical portion of the ignition switch also provides power to the starter motor to start the engine.

The ignition lock is an anti-theft device that prevents a vehicle from being driven unless the ignition key is in the ignition switch. If the ignition key is not in the ignition switch, it 's impossible to turn the steering wheel.

To replace the ignition switch cylinder lock, the trim panels around the steering wheel are removed. Then the tamper-proof hardware that attaches the ignition lock assembly to the steering column is removed. The ignition lock assembly is removed from the steering column, and the lock cylinder is replaced. The new ignition lock is reattached to the steering column, and the trim panels are replaced.
About this Repair: Ignition Switch (Lock Cylinder)

Why this happens:

* A broken ignition lock can make it difficult to turn the key.

* A failed ignition switch can result in the engine continuing to run even after the key has been removed from the ignition.

* Sometimes when there is a problem with the ignition switch, the steering wheel is difficult to lock or unlock.

Price range for Labour of Ignition Switch Lock Cylinder Replacement: £0.00 - £0.00



Return to the top of the page
Ignition Wire Set Replacement

The ignition coil generates the "spark" required to ignite gasoline. The ignition wire set (also known as the spark plug wires) conducts the spark generated by the ignition coil to the ignition distributor.

As the engine rotates, it operates the ignition distributor, synchronizing the delivery of the spark to the corresponding spark plug in each engine cylinder. The ignition wire set conducts the spark from the ignition cap to the spark plugs. To maintain synchronization, it is best to replace the spark plug wire set one wire at a time.

To replace a spark plug wire, the wire is removed from the distributor cap at one end and from the spark plug at the other end, then replaced.

Correct routing of the ignition wire set is critical to ensure that the spark plug wires don’t come into contact with rotating engine components or rest on the hot exhaust manifold.

Depending on what is required, the spark created by the ignition system ranges from 12,000 to 45,000 volts. Due to the high voltage, it’s critical that ignition system components are well insulated. If insulation breaks down, the spark never arrives at the spark plug, causing the engine to run poorly—or not at all.
About this Repair: Ignition Wire Set Replacement

Recommendations:

* We recommend considering replacing the ignition wires if they have more than 60,000 miles on them and any other component of the ignition system is exhibiting wear or needs replacement.

Why this happens:

* Ignition wire failure can be caused by failures elsewhere in the ignition system. The ignition coils and spark plugs should be thoroughly inspected and tested.

* Oil or coolant leaks can damage ignition wire. The leaks need to be repaired along with the ignition wires.

* Failing ignition wires can cause the engine to run roughly or to lack power when accelerating.

* Failing ignition wires can result in an engine trouble code and a dashboard warning light.

Price range for Labour of Ignition Wire Set Replacement: £0.00 - £0.00



Return to the top of the page
Lower Radiator Hose Replacement

An engine has two radiator hoses: lower and upper. The lower hose brings coolant (a mixture of water and antifreeze) that has been cooled in the radiator to the engine, where it circulates and absorbs heat. The upper hose carries hot coolant from the engine back to the radiator to be recooled. The radiator hoses are located between the radiator and the engine block.

Radiator hoses are made from rubber so they deteriorate over time. Periodically check for cracks, damage, swelling, or contamination due to oil leaks.

To replace a radiator hose, the cooling system is drained. The clamps securing the radiator hose are removed, and the hose is replaced. The radiator is filled with coolant, air is removed from the system, and the engine is started and brought to normal operating temperature.
About this Repair: Radiator Hose Replacement - Lower

Recommendations:

* We recommend also replacing the thermostat and the radiator cap.

* The entire cooling system should be inspected and tested when the radiator is replaced.

* The entire cooling system and all coolant-carrying hoses should be inspected when replacing radiator hoses.

* We recommend using moulded radiator hoses rather than "universal" hoses. Universal hoses can be deformed by pressure and heat and are prone to failure earlier than hoses designed to fit your vehicle.

Why this happens:

* A failing radiator can cause the engine to run hot or overheat.

* Radiators require replacement due to corrosion and leaking.

Price range for Labour of Lower Radiator Hose Replacement: £0.00 - £0.00



Return to the top of the page
Mass Airflow Sensor Replacement

The mass air flow (MAF) sensor measures the amount of air entering the engine. Based on input from the MAF sensor, a computer determines how much fuel should be injected into the engine. The sensor is usually located on or in close proximity to the air filter housing.

Problems with mass air flow sensors are common. A bad or contaminated sensor can cause a wide range of problems, including stalling (especially when the engine is cold), misfiring, and poor acceleration. A problem with the MAF sensor often causes the check engine or service engine soon light on the dashboard to illuminate.

To replace the MAF, the electrical connection and screws (or clamps) securing the sensor are removed, and the new sensor is installed.
About this Repair: Mass Airflow Sensor Replacement

What to watch out for:

* Mass Airflow Sensors are often replaced when the only problem is a bad connector or the sensor wiring harness. The shop should check these items before replacing the sensor.

* "High-performance" wet foam air filters are not recommended because they will damage the mass airflow sensor and actually cause poor performance.

Recommendations:

* The air filter should be replaced along with the Mass Airflow Sensor. Dirt and debris should be cleaned out of the system to prevent any damage to the new sensor.

Why this happens:

* A failing mass airflow sensor can cause the "Check Engine Light" to come on and due to high nitrous oxide, the vehicle may fail an emissions test.

* If the Mass Airflow Sensor is not functioning correctly, the vehicle may lack power when accelerating or going up hills.

Price range for Labour of Mass Airflow Sensor Replacement: £0.00 - £0.00



Return to the top of the page
Oil Pump Replacement

The engine oil pump generates the oil pressure needed to keep internal engine parts lubricated. If the oil pump fails, major engine damage can occur.

The oil pump may be located in the oil pan or operated by the timing belt (or timing chain).

* If the oil pump is located in the engine oil pan, the pan must be removed to replace the oil pump.

* If the timing belt operates the oil pump, the engine's fan belts and timing components must also be removed in order to gain access to the oil pump.

* If the oil pump is driven directly by the crankshaft, the accessory belts, timing cover, timing belt, and crankshaft pulley must be removed in order to access the oil pump.

Price range for Labour of Oil Pump Replacement: £0.00 - £0.00



Return to the top of the page
PCV Valve Replacement

The positive crankcase (PCV) ventilation valve is a one-way valve in a car's pollution control equipment. It ensures that gases are continually evacuated from the engine. A defective PCV valve can cause an to run poorly or to leak oil.

The PCV valve circulates engine oil vapour containing gasoline fumes back into the engine to be burned, thus lowering emissions. The PCV valve also extends the life of the engine and oil. As the PCV valve constantly recirculates the air through the crankcase, it helps remove moisture that could cause sludge to form.

The PCV valve should be replaced every 30,000 to 50,000 miles (see your vehicle owner’s manual for specific service intervals). PCV valve failure may cause an engine to stall or run rough. A faulty PCV valve may cause high emission levels, which could result in a vehicle failing a state's smog test.

The PCV valve is normally located at the top of the engine. To replace it, the PCV hoses are removed, and the PCV valve is removed from the intake manifold (or valve cover). A new valve is installed and the hoses re-attached.
About this Repair: PCV Valve Replacement

Recommendations:

* The engine should be tested to verify normal operation after a PCV repair to ensure that no additional problems exist that may have contributed to PCV failure.

* If any oil leaks are found, all the hoses and breathers in the PCV system should also be inspected and replaced.

Why this happens:

* Failed PCV valves can cause the engine to idle roughly and can cause the "Check Engine Light" to illuminate.

* PCV valves are a regularly scheduled maintenance item and are replaced to keep the engine running optimally.

* PCV systems are occasionally updated by the manufacturer. Your shop should update your system if an update is available.

Price range for Labour of PCV Valve Replacement: £0.00 - £0.00



Return to the top of the page
Radiator Replacement

The engine generates heat when it is running; this heat must be removed to prevent damage to the engine. Coolant circulates throughout the engine and absorbs this heat. The water pump pushes the coolant through the radiator (where it is cooled) and returns it to the engine once more to absorb the engine’s heat, before returning it to the radiator to be cooled again.

When a vehicle is travelling fast, rushing air flows through the radiator and cools the engine. When a vehicle is in stop-and-go traffic or stuck at a traffic light, the engine’s cooling fan pushes air through the radiator.

Periodic flushing of the cooling system is required to prevent the radiator and coolant passages from becoming plugged up due to debris circulating in the cooling system.

The radiator should be replaced if it develops a leak or no longer dissipates heat efficiently. To replace the radiator, the technician drains the coolant from the radiator and removes the radiator and radiator hoses from the vehicle. When applicable, the cooling fan switch and electric cooling fan assemblies are transferred to the new radiator. Once the new radiator is installed, it is filled with fresh coolant.

Mechanics' Corner: More Technical Detail

Removal of the front bumper, as well as removal of engine bay components such as hoses, ducting, and additional plumbing are often required in the course of this repair. To avoid trapped air bubbles in the cooling system, special procedures may be required.
About this Repair: Radiator Replacement

Recommendations:

* We recommend also replacing the thermostat and the radiator cap.

* The entire cooling system should be inspected and tested when the radiator is replaced.

Why this happens:

* A failing radiator can cause the engine to run hot or overheat.

* Radiators require replacement due to corrosion and leaking.

Price range for Labour of Radiator Replacement: £0.00 - £0.00



Return to the top of the page
Spark Plugs Replacement

Spark plugs are part of the vehicle's ignition system; they contain two electrodes across which electricity jumps to produce a spark that ignites the gas in the engine. The energy caused by the combustion is converted into energy used to power the wheels.

Spark plugs generally come one per engine cylinder and are replaced every 30,000 to 60,000 miles.

Worn spark plugs can cause poor fuel economy, poor drivability, difficulty starting the engine, and high pollution emissions.

To replace the spark plugs, the spark plug wire or ignition coil is removed from each spark plug. The spark plug is unscrewed from the engine, and a new spark plug is installed.

Mechanics' Corner: More Technical Detail

Access to the spark plugs can be very limited on modern vehicles. Some require the removal of major components—the intake manifold, pipes, and hoses—while others can be straightforward.

Price range for Labour of Spark Plugs Replacement: £0.00 - £0.00



Return to the top of the page
Thermostat Replacement

The thermostat is a valve that keeps coolant circulating in the engine until it reaches normal running temperature. When this happens, the thermostat opens and allows coolant to flow to the radiator. If the thermostat fails to open, the engine will overheat. If the thermostat sticks open, the engine will take longer than normal to reach operating temperature, causing poor heater performance, higher exhaust emissions, and on some vehicles, the check engine light to illuminate.

To replace the thermostat, the cooling system is drained, the radiator hose is removed from the thermostat housing, and the housing is removed from the engine. The thermostat and its housing gasket are replaced, the housing and hose are reassembled, and the cooling tank is filled with fresh coolant.
About this Repair: Thermostat Replacement

Recommendations:

* The entire cooling system should be inspected and tested when the thermostat is replaced.

* A high-quality and original thermostat should be used. Poor quality thermostats may not function properly and can cause engine damage or damage to components of the emission system.

Why this happens:

* A failed thermostat can cause the vehicle to run hot and can cause the "Check Engine Light" to illuminate.

* When the thermostat fails, a sudden drop in fuel economy may occur.

* If the new thermostat does not immediately resolve engine temperature problems, another cooling system component is likely failing.

Price range for Labour of Thermostat Replacement: £0.00 - £0.00



Return to the top of the page
Timing Belt Replacement

Driven by the crankshaft, the timing belt keeps internal engine components in sync by causing valves to open and close at the proper time.

In order to maintain the mechanical integrity the engine needs to operate, engine components must be in precise synchronization. If the timing belt is loose or improperly adjusted, it may "jump time" (skipping a tooth or more, usually on the cam gear). This results in a loss of synchronization and engine performance.

In addition, because the timing belt is made from rubber and reinforced with fibre cords, it naturally degrades over time. It should be replaced at scheduled intervals, which vary among car manufacturers, but are usually every 60,000 to 90,000 miles.

In some cases, when the timing belt fails, the engine will simply stop running; replacing the belt will fix the problem.

Some engines cannot tolerate any deviation in precise valve control (e.g. a loose belt, skipped tooth, belt separation, or breakage). In these engines, timing belt failure can have disastrous consequences. These belt-related problems can cause major engine damage, such as damaged pistons and bent valves. The Check Engine Light may illuminate with a fault stored in the computer relating to timing deviation. In extreme cases, the timing belt may be audibly loose and noisy prior to failure; however, a worn belt can fail without warning. Timing belt maintenance and replacement intervals must be followed diligently.

To replace the timing belt, remove the fan belts, pulleys, crankshaft pulley, and timing covers. When replacing the timing belt, the mechanic also inspects components inside the timing cover and, if necessary, replaces oil seals, tensioners, and idler bearings. On certain engines, a water pump replacement should be done at the same time as the timing belt. The timing belt and timing belt idler are considered a unit and should be replaced at the same time.

Price range for Labour of Timing Belt Replacement: £0.00 - £0.00



Return to the top of the page
Timing Chain Replacement

The timing chain keeps internal engine components in sync with each other by causing valves to open and close at the proper time. It is durable and generally needs no maintenance. However, timing chain failure can result in serious internal engine damage.

In order to maintain the mechanical integrity the engine needs to operate, engine components must be in precise synchronization. If the timing belt is loose or improperly adjusted, it may "jump time" (skipping a tooth or more, usually on the cam gear). This results in a loss of synchronization and engine performance.

Due to their inherent long life, timing chains usually have no specific replacement or maintenance intervals. Abnormal engine noise originating at the front of the engine (a rattle or rumble, associated with engine speed) is a good indicator of a failing timing chain. Timing chain faults can cause poor engine performance with or without Check Engine Light illumination. Some engines cannot tolerate any deviation in precise valve control. Any timing chain problem—a loose, noisy, or broken timing chain—can have disastrous consequences. Repairs can range from simple timing chain replacement to major engine repairs for damaged pistons and bent valves.

To replace the timing chain, remove the fan belts, pulleys, crankshaft pulley, and timing covers. The mechanic will inspect components inside the timing cover and, if necessary, replace oil seals, tensioners, and idler bearings. On certain engines, a water pump replacement should be done at the same time as the timing chain. The timing chain, its tensioner, and sprockets are considered a unit and should be replaced at the same time.

Price range for Labour of Timing Chain Replacement: £0.00 - £0.00



Return to the top of the page
Upper Radiator Hose Replacement

An engine has two radiator hoses: upper and lower. The upper hose carries hot coolant (a mixture of water and antifreeze) from the engine to the radiator to be cooled. The lower hose brings coolant that has been cooled in the radiator to the engine, where it circulates and absorbs heat. The radiator hoses are located be engine.

Radiator hoses are made from rubber so they deteriorate over time. Periodically check for cracks, damage, swelling, or contamination due to oil leaks.

To replace a radiator hose, the cooling system is drained. The clamps securing the radiator hose are removed, and the hose is replaced. The radiator is filled with coolant, air is removed from the system, and the engine is started and brought to normal operating temperature.
About this Repair: Radiator Hose Replacement - Upper

Recommendations:

* We recommend replacing the hose clamps, as the clamps will weaken over time and new clamps will help prevent coolant leaks.

* Leaking or swollen radiator hoses need to be replaced to prevent the failure of the cooling system.

* Radiator hoses can be damaged by oil leaks and need to be replaced if they are cracked or soft.

* The entire cooling system and all coolant-carrying hoses should be inspected when replacing radiator hoses.

* We recommend using moulded radiator hoses rather than "universal" hoses. Universal hoses can be deformed by pressure and heat and are prone to failure earlier than hoses designed to fit your vehicle.

Price range for Labour of Upper Radiator Hose Replacement: £0.00 - £0.00



Return to the top of the page
Valve Clearance Check and Adjust

Heat produced in the engine causes internal engine components to expand and contract. As the engine heats up, proper valve clearance is essential for optimal performance.

Engines are made of many different materials and metals. Each material expands at a different rate and each engine component is subjected to different levels of heat. Manufacturers design engines to have space between components so that the various components can rotate and function.

To avoid premature wear of internal engine components, it is critical to maintain correct valve clearance. Incorrect clearances can cause the engine’s intake and exhaust valves to fail prematurely, which can lead to engine idle and drivability problems, as well as excess pollution.

The recommended interval for checking valve clearance varies among manufacturers. To check and adjust the valve clearances, the valve cover is removed, the engine is manually rotated, and each valve clearance is measured and adjusted as required.

Mechanics' Corner: More Technical Detail

To ensure longevity and proper operation, the engine valves require a specific amount of clearance (sometimes referred to as "lash"). Extremes of insufficient or a lack of clearance will cause a valve to run hot and leak. A valve that is extremely loose with excessive clearance can suffer from mechanical wear and be noisy. Either insufficient or excessive clearance can cause poor engine performance or failure.

Valve clearance adjustment can be a regular maintenance procedure. On most modern vehicles, however, the proper adjustments are maintained automatically through the design of the valve train (specifically the hydraulic lifter).

The purpose of a valve adjustment is to bring the clearance between the tip of valve stem and the camshaft lobe or rocker arm back in to the specified clearance that was determined by the design engineer. As the camshaft rotates, it pushes on the valve stem either directly or by using a lever such as a rocker arm, to open the valves inside the combustion chambers at the proper time. The valves are closed automatically by the valve springs.

If the valve clearance is too small, the valves will never fully close when they should be doing so and this will eventually burn part of the valve surface off and cause a constantly misfiring engine. If the valves are too tight, the vehicle may also exhibit rough running characteristics either cold, hot or all the time. If the valve clearances get too loose, this will lead to a noisy running engine and will eventually damage the camshaft lobes, rocker arms ( if equipped ) and the tips of the valves themselves.

Price range for Labour of Valve Clearance & Adjustment: £0.00 - £0.00



Return to the top of the page
Valve Cover Gasket Replacement

Internal engine components are lubricated with oil. Engines have many seals and gaskets that prevent oil from leaking out of the engine. The valve cover gasket is located on the top of the engine. It prevents oil from leaking onto the hot exhaust system, which could cause a fire.

Gaskets deteriorate over time, allowing engine oil to leak. An oil leak can not only cause a fire but also can drain your engine of oil, which can cause serious engine damage.

To replace the valve cover gasket, the technician removes the bolts securing the valve cover to the engine. S/He removes and cleans the valve cover, and then replaces it.
About this Repair: Valve Cover Gasket(s) Replacement

What to watch out for:

* Components such as spark plug and PCV seals and grommets can also leak oil, which can be mistaken for a leaking valve cover gasket. These components should be replaced along with the valve cover gasket.

Recommendations:

* Using high-quality valve cover gaskets will reduce the chance of recurring leaks and additional repairs.

Why this happens:

* Valve cover gaskets need to be replaced when they begin to leak oil, which can damage other engine components, especially belts and hoses.

* Oil leaking from valve cover gaskets can result in a burning smell coming from under the hood.

* When replacing the valve cover gasket, we recommend having a valve adjustment performed, if possible. Doing so will save labour costs.

Price range for Labour of Valve Cover Gasket Replacement: £0.00 - £0.00



Return to the top of the page
Valve Job

A valve job is an inspection, machining and sometimes replacement of the valves, valve train, valve guides, valve springs, valve seats, lifters and camshaft(s) in order to bring all these components back to the factory original or even enhanced operating specifications.



Return to the top of the page
Water Pump Replacement

The water pump pushes coolant through a vehicle's cooling system. The water pump is operated by a fan belt at the front of the engine or by the timing belt.

A failing water pump may start to leak coolant and/or make a rumbling sound as the water pump's bearings start to deteriorate.

To replace the water pump, the cooling system is drained and the fan belt or timing belt and pulleys are removed.

If the water pump is operated by a fan belt, the hose going from the water pump to the radiator is removed, as are the bolts securing the water pump to the engine. The water pump is removed from the engine, and the engine surfaces are cleaned. A new water pump and gasket are installed, and the cooling system is refilled with fresh coolant.

If the water pump is operated by the timing belt, the timing belt covers, timing belt, and all related components are disassembled. The hardware securing the water pump to the engine is removed, and the water pump is removed from the engine. The surfaces are cleaned and a new water pump and gasket are installed. All timing belt–related components, fan belts, and pulleys are reinstalled, and the cooling system is refilled with fresh coolant.
About this Repair: Water Pump Replacement

Recommendations:

* When replacing the timing belt, we recommend replacing the water pump if it is driven by the timing belt. Doing so will reduce labour cost and optimize engine performance.

* You may want to consider replacing drive belts along with the water pump if they have not been recently replaced.

* The entire cooling system and all coolant-carrying hoses should be inspected when replacing the water pump.

Why this happens:

* Water pumps require replacement if they begin to leak coolant. Leaking water pumps may result in damage to the drive belts and the timing belt.

* A failed water pump is often due to problems in the cooling system, such as a failing thermostat, radiator, seals, or even head gaskets.

Price range for Labour of Water Pump Replacement: £0.00 - £0.00



Return to the top of the page
Accelerator Cable

The accelerator cable is a braided steel cable in a plastic housing that connects the accelerator pedal to the engine throttle body so that the driver can command more or less power from the engine by applying or releasing foot pressure.



Return to the top of the page
Cam Sprocket

A cam sprocket is a belt driven sprocket that is attached to the end of the camshaft. It is engaged and rotated by the timing belt that is connected to a sprocket on the end of the crankshaft.



Return to the top of the page
Camshaft

A camshaft is a long belt, chain or gear driven shaft with machined elliptical lobes for each intake and exhaust valve contained in the engine. As the camshaft rotates inside the engine, the elliptical lobes push and release mechanisms that precisely open and close the valves of the engine.



Return to the top of the page
Camshaft Actuator

A camshaft actuator is a mechanical or electronic device that is mounted onto the end of a camshaft whose purpose is to slightly advance or retard the timing of when the camshaft opens or closes the intake and/or exhaust valves in order to optimize engine power while at the same time reducing emissions.



Return to the top of the page
Camshaft Seal

The camshaft seal seals the camshaft as it rotates, preventing engine oil from leaking out of the engine.



Return to the top of the page
Camshaft Sensor

By tracking a rotating identification mark that tells it each time the cylinder firing order begins the camshaft sensor is able to tell the ignition module which cylinder is in the proper position to be 'fired'. This information also enables the ignition module to slightly advance or retard the 'timing' of the spark to each cylinder in order to compensate for different engine operating conditions such as temperature and load or the engine speed as reported by the crankshaft sensor. The camshaft sensor is usually mounted near the camshaft. In some cases it is mounted inside the distributor.



Return to the top of the page
Carburettor

A carburettor is a device that mixes fuel with the incoming vortex of air as it enters the engine and goes in to the cylinders. It usually has 7 or more circuits that combine the appropriate amount of fuel with the incoming air relative to the constantly changing demands being placed on the engine.



Return to the top of the page
Coolant

Coolant is a mixture of an antifreeze agent (ethylene glycol or propylene glycol), water, and a small amount of corrosion inhibitor. Manufacturer-specified and proprietary coolant brands are becoming common. Make sure to use the coolant the manufacturer recommends; the wrong coolant can damage your car.



Return to the top of the page
Coolant Expansion Tank

As the engine heats up, coolant expands. The coolant expansion tank provides additional storage for coolant as it expands. This is also where coolant is added to your engine.

Be extremely cautious when removing the cap from the expansion tank when the engine is warm!



Return to the top of the page
Cooling Fan Motor

The cooling fan motor is an electric motor that turns the fan blades to draw air across the radiator. Some vehicles may use multiple electric fans for better control of the cooling system.

For the most part, electric cooling fans are controlled by the same computer that controls the engine. However, in some engines, the fans are turned on and off by a temperature-sensitive switch mounted either in the radiator or elsewhere in the cooling system. The use of compact and modern electrically-driven cooling fans has replaced the previous system of belts and pulleys.



Return to the top of the page
Crankcase

The crankcase is the large, open cavity in the bottom of an engine where the crankshaft is mounted and rotates in a bath of lubricating oil.



Return to the top of the page
Crankshaft

The crankshaft is a large, rotating metal shaft that is mounted on the bottom of the engine and is the length of the engine. As it rotates, offset crankshaft journals raise and lower the connecting rods and pistons in the cylinders.



Return to the top of the page
Crankshaft Angle Sensor

The crankshaft angle sensor measures the rotation speed and location of the crankshaft. This information is used by the fuel and ignition systems. Starting issues that are difficult to diagnose are commonly traced to intermittent or random faults in the crank angle sensor or its wiring and connections.

Mechanics' Corner: More Technical Detail

The crankshaft sensor can be mounted near the crankshaft itself or inside the distributor. It measures the speed and revolutions of the crankshaft and sends this information to the ignition module, which uses the information to determine when to fire the ignition coil.



Return to the top of the page
Crankshaft Pulley

The crankshaft pulley is a weighted and balanced pulley that is mounted on the end of the crankshaft, whose purpose is to turn the drive belts that operate the alternator, the power steering pump and the air conditioning compressor.



Return to the top of the page
Crankshaft Seal

The crankshaft seal closes the openings on either end of the crankshaft. Keeping the crankcase closed prevents engine oil from leaking out of the engine.



Return to the top of the page
Cylinder Head

The cylinder head is a large rectangular piece of metal that is installed on top the cylinders and consists of a platform that contains the valves and part of the combustion chamber. Ports, or passages, in the cylinder head direct intake flow into the combustion chamber and exhaust gases out into the exhaust.



Return to the top of the page
Drive Belt/Fan Belt

Drive belts are part of a belt/pulley system that is driven by the engine crankshaft to run such items as the AC compressor, alternator, and power steering pump. Previously, the "V" profile was the universal drive belt design, but more modern vehicles use the flat "ribbed" design, often referred to as a serpentine belt.

Some highly sophisticated, modern vehicles have eliminated all drive belts by providing engine-driven internal shafts. Cooling fans, with few exceptions, are now run by compact electric motors.



Return to the top of the page
Electronic Throttle Unit

Many vehicles now have an electronically controlled throttle system. The accelerator pedal senses the pedal position, sends this signal to the engine control unit, and activates the electronic throttle module, which controls the vehicle's speed.

Other vehicles utilize the traditional cable plus an electronic throttle unit as the link between the throttle pedal and throttle. This design informs the engine control unit of throttle position information and allows the engine control unit to adjust engine idle speed functions via a simple motor control incorporated into the electronic throttle unit.

The electronic throttle module also controls engine idle speed and cruise control.



Return to the top of the page
Engine Block

The engine block is a machined casting in which the crankshaft is installed and contains the individual cylinders in which the pistons move up and down.



Return to the top of the page
Engine Control Unit

The vehicle's engine control unit (ECU) is a computer that receives information from sensors in the engine. The computer processes this information and makes calculations to control ignition timing, fuel-delivery parameters, engine idle speed, and pollution emitted from the vehicle. The control unit interacts and makes mutual decisions with systems throughout the vehicle. On newer vehicles, the ECU may also control the engine cooling fans, cruise control, and AC.



Return to the top of the page
Engine Coolant Temperature Sensor

The engine coolant-temperature sensor measures the engine coolant temperature.

The engine control unit uses the data to control the amount of fuel delivered to the engine, the ignition timing, the engine cooling fan, and many of the emission controls.



Return to the top of the page
Engine Cooling Fan

To enhance and control air flow through the radiator, all vehicles use one or more engine cooling fans.

Modern vehicles with electrically-driven fans utilize various electronic control strategies to provide either multiple or infinitely variable fan speeds, which assists a rapid warm up and steady operating temperatures.

Although crude by comparison, belt-driven fans often utilize temperature-sensitive "couplings" to reduce fan speed at start up to provide more fan engagement as the temperature increases.



Return to the top of the page
Engine Cylinder

The engine cylinder is a machined round bore (tube) inside the engine block that houses the piston as it moves up and down, producing compression.



Return to the top of the page
Engine Oil

Engine oil provides lubrication for—and conducts heat away from—internal engine components. Currently, there is a wide selection among brands, oil composition, and weights of motor oil. Check your vehicle's requirements—the wrong motor oil can damage the engine.



Return to the top of the page
Engine Oil Pressure Switch

When engine oil pressure drops below three to six pounds per square inch (PSI), the engine oil pressure switch illuminates a light on the dashboard to alert the driver that the oil pressure is below what is needed to prevent serious internal engine damage. Some engines use multiple oil pressure switches or variable oil pressure switches/sensors that also incorporate a dashboard display or gauge.



Return to the top of the page
Engine Valve

An engine valve is a machined metal disk with a stem, called the valve stem. Intake or exhaust gases flow into and out of a combustion chamber by opening and closing intake or exhaust valves.



Return to the top of the page
Flex Plate

The flex plate is a stamped metal disk that mounts the torque converter to the rear end of the crankshaft. In some cases it contains a ring gear for the starter.



Return to the top of the page
Flywheel

The flywheel is a large machined and balanced heavy metal disk that mounts on the rear end of the crankshaft whose purpose is to absorb the shock caused by the firing of the cylinders and provide a surface to which the clutch disc can engage. It also has toothed ring gear that provides an engagement point for the starter motor.



Return to the top of the page
Fuel Filter

The fuel filter removes dirt and debris from the fuel system, preventing damage to the fuel pump, fuel injectors, and the fuel pressure regulator.

Many vehicles also use a screen- or "sock"-type filter in the fuel tank. Any restriction at this or the main fuel filter location can cause performance issues such as poor performance when climbing hills or under acceleration. Blocked fuel filters can cause engine moaning noises. Due to extended replacement intervals, fuel filters tend to be overlooked during diagnostic procedures.



Return to the top of the page
Fuel Injector

The fuel injector is a nozzle-and-valve system that injects gas into the engine.



Return to the top of the page
Fuel Injector Seals

To prevent fuel leakage, each fuel injector is provided with a seal (usually of an O-ring design) at the fuel line attachment. A similar seal at the injector hose provides an airtight seal at the fuel injector's connection to the intake manifold. Neither seal should be reused if the fuel injector is removed or replaced.



Return to the top of the page
Fuel Pump

The fuel pump creates pressure in the fuel lines, which pushes gasoline through the fuel injectors and into the engine. Unlike engine-mounted, mechanically-driven fuel pumps of the past, modern fuel pumps are self-contained units, independently mounted away from the engine. All modern fuel pumps incorporate an electric motor and many are installed in the fuel tank (where they are constantly immersed in fuel).



Return to the top of the page
Glow Plug

The glow plug is an electrically heated, thin metal probe that warms the air and diesel fuel mixture in the combustion chambers in order to aid in the initial start up of a cold diesel engine.



Return to the top of the page
Head Gasket

The head gasket is situated between the flat surfaces of the cylinder head and the engine block. The head gasket can consist of a composite material, a multi-layer metal "sandwich" design, or a one-piece, copper-like material.

The head gasket is critical—it must contain intense combustion pressure and temperature, extremely hot engine coolant, and equally hot engine oil under pressure. The head gasket must prevent both internal and external leakage. The clamping force applied to the head gasket is extreme by design—the cylinder head and engine block must be flat and true. In addition, the cylinder head bolts must be correctly installed or "torqued" as specified. An "inline" engine design requires one head gasket. "V" and flat engine designs require two head gaskets.



Return to the top of the page
Idle Air Bypass Kit

An idle air bypass kit is a computer controlled electronic shutter valve that allows measured amounts of air around the throttle plate to increase or decrease the engine idle speed in response to the loads being applied.



Return to the top of the page
Idle Speed Control Motor

An idle speed control motor is a computer controlled, geared stepper motor with a plunger that pushes against the throttle body bell crank in order to raise or lower the engine idle in response to the loads being applied.



Return to the top of the page
Ignition Cap and Rotor

Sometimes referred to as Ignition Cap and Rotor, Ignition Cap, Replace Cap, Replace Ignition Cap, Ignition Cap Replace, Cap Replace

The ignition (or distributor) cap and rotor are housed in the vehicle's ignition system. As part of the ignition distributor, they allow each spark to be "distributed" from the ignition coil to the ignition wires and then to each spark plug.

When the engine is running, high voltage created by the ignition coil travels to the ignition cap and then through the coil wire and ignition rotor. As the ignition rotor turns in the distributor, the rotor distributes the spark by sending it in a synchronized order through the spark plug wires to the spark plugs, located in each of the engine's cylinders.

Depending on the type of ignition system, the spark can range from 12,000 to 45,000 volts. Due to the high voltage, it’s critical that ignition system components are well-insulated. If insulation breaks down, the spark never arrives at the spark plug, causing the engine to run poorly—or not at all.

Be sure to inspect and/or replace the cap and rotor every 30,000 miles to avoid engine drivability problems.

Note: Engines utilizing multiple coil packs—also known as a coil-on-plug (COP) ignition—do not use an ignition distributor.
About this Repair: Ignition Cap and Rotor Replacement

Recommendations:

* The ignition cap and rotor should always be replaced as a set.

Why this happens:

* Ignition cap and rotor failure can be caused by failures elsewhere in the ignition system. The ignition wires and spark plugs should be thoroughly inspected. Old plugs or wires will burn out even a new cap and rotor.

* Engine fluid leaks can cause damage to the ignition cap and rotor; these leaks should be repaired when the cap and rotor are replaced.

* A failing ignition cap and rotor can cause an engine to be hard to start and to run roughly. It can also cause the "Check Engine Light" to be lit.

Price range for Labour of Ignition Cap & Rotor Replacement: £0.00 - £0.00



Return to the top of the page
Ignition Coil

The ignition (or spark) coil converts low battery voltage into the higher voltage needed to produce a spark with the capacity to ignite the gasoline in the engine. An engine can have one ignition coil or one ignition coil per cylinder.

Mechanics' Corner: More Technical Detail

The ignition coil is a small electrical transformer that converts the high amperage 12-volt output of the vehicle's electrical system into a low amperage but very high direct current (DC) voltage that ranges from 5,000 to 80,000+ volts. This is done with two sets of windings (primary and secondary) made up of very small, hair-like copper wire.

Primary Windings
Using the positive and negative terminals on the ignition coil, the primary windings are saturated with system voltage. As the energy in the primary windings surrounds the iron core, a strong magnetic field (or flux) is created. Once the primary windings are filled by current and/or when voltage-limiting devices activate to prevent the ignition coil from overheating, the flow of current to the coil is limited.

Secondary Windings
When the flow of current to the coil has been limited (by switching off the negative side of the coil), the stored energy collapses onto the grounded secondary windings (all electricity seeks ground in order to complete or balance a circuit). However, these secondary windings are vastly different from the primary windings because they have a much higher electrical resistance. This higher electrical resistance causes a transformation of the low voltage into a high voltage that electrically penetrates the secondary windings and finds the grounded path.



Return to the top of the page
Ignition Coil Boot

A coil boot is a 4-6 inch electrically insulating rubber boot containing an electrical contact spring which connects the secondary coil terminal to the centre electrode of a spark plug in a 'coil over' ignition system.



Return to the top of the page
Ignition Lock Assembly

The ignition lock is an antitheft device that prevents a vehicle from being driven unless the key is in the ignition switch and turned to the "on" position. If the key is not in the "on" position, it is impossible to turn the steering wheel. The assembly includes the ignition lock cylinder into which the key fits.



Return to the top of the page
Ignition Lock Electrical Assembly

The ignition lock electrical assembly supplies electric power to auto components, such as the radio and electric windows. When the key is turned in the ignition switch, the assembly also powers the fuel pump and components needed to start and run the engine.



Return to the top of the page
Ignition Module

The ignition module is the device that interrupts the ground side of the ignition coil in order to create the necessary voltage spike that is delivered to the spark plugs. The ignition module is a robust power transistor that has logic circuits that evaluate and decide when the ignition module should signal the ignition coil to fire. There are one or more sensors that send this information to the logic circuit for it to evaluate. The ignition module is located near the ignition coil or inside the engine computer.



Return to the top of the page
Ignition Switch

The ignition switch controls the availability of voltage to the positive side of the ignition coil. This occurs anytime the ignition switch is in the start or run position. When the ignition switch is in the accessory position, there is no voltage supplied to the coil thus limiting the amount of energy draining from the battery while someone just listens to the radio.



Return to the top of the page
Ignition Wire Set

The ignition (or spark plug) wire set takes the ignition spark from the ignition cap and delivers it to the spark plugs. These wires wear out over time and can cause the engine to run roughly. It is common to have to replace the wire set once or twice during the vehicle's life.

Note: Engines utilizing multiple coil packs—also known as a coil-on-plug (COP) ignition—do not use ignition/spark plug wires.



Return to the top of the page
Lower Radiator Hose

An engine has two radiator hoses—lower and upper. The lower hose brings coolant (a mixture of water and antifreeze) that has been cooled in the radiator to the engine, where it circulates and absorbs heat. The upper hose carries hot coolant from the engine back to the radiator to be re-cooled. The radiator hoses are located between the radiator and the engine block.

Radiator hoses are made from rubber and will deteriorate over time. Periodically check for cracks, damage, swelling, or contamination due to oil leaks. Some manufacturers specify replacement intervals for radiator hoses.



Return to the top of the page
MAP Sensor

The MAP Sensor, or Manifold Absolute Pressure Sensor measures the pressure of the intake system, and with this and other information the engine control module can determine the amount of air entering the engine. The engine control module then knows the exact amount of fuel to add to the get the proper air/fuel mixture.



Return to the top of the page
Mass Airflow Sensor

The mass airflow sensor generates an electrical signal based on the mass or weight of air entering the engine. This signal is continuously monitored by the engine electronic control unit, which adjusts the corresponding amount of fuel to maintain the air/fuel ratio. These adjustments are commonly called "fuel trim."

A failing mass airflow sensor can cause an incorrect fuel trim setting, which leads to poor performance and possible Check Engine Light illumination.



Return to the top of the page
O-Ring

An O-ring is typically a neoprene rubber ring that is used to seal and prevent fluid loss when two surfaces are bolted or pressed together, such as a thermostat housing to an intake manifold.



Return to the top of the page
Oil Cooler

An oil cooler is a small oil cooling radiator that is typically mounted in front of the engine radiator.



Return to the top of the page
Oil Drain Plug Gasket

The drain plug gasket prevents oil leaks from the drain plug. The screw-in drain plug is a simple design that includes a "soft" washer-like gasket situated between the oil pan and oil drain plug. This gasket/washer can be made of copper, aluminium, or a fibre composition. The drain plug gasket/washer should not be reused.



Return to the top of the page
Oil Filter

The engine oil filter removes harmful deposits from the engine oil before they can be circulated throughout the engine.

At one time, oil filters were as basic as a non-replaceable screen. However, as engine design evolved, filters utilizing a separate, replaceable filter element (usually with a pleated paper design) became common.

This evolved to the one-piece, spin-on metal cartridge used today. The latest designs are once again using a separate, replaceable filter element of a pleated paper design. The current design was developed to reduce environmental waste.



Return to the top of the page
Oil Pan

An oil pan is a large cast or sheet metal container that mounts to the bottom of the engine block that serves as the reservoir for the engine oil. Some automatic transmissions have a pan to contain the automatic transmission fluid.



Return to the top of the page
Oil Pan Gasket

The engine lubrication system requires a large volume of oil. This supply of oil (typically one to two gallons) is contained in the oil pan.

The oil pan—made of stamped steel or aluminium casting—is mounted at a low point in the engine configuration where oil naturally accumulates. The oil pan gasket provides a seal at the attachment between the engine block and the oil pan. The oil pan gasket can be the common cork/composite type, an elastic O-ring design, or the increasingly common silicone-type sealant that is applied during engine assembly.

Due to its location in the vehicle, the oil pan is vulnerable to damage caused by curbs, debris, and off-road excursions.

Mechanics' Corner: More Technical Detail

Mounting the oil pan at the low point in the engine configuration is known as a "wet sump." A technically superior design that eliminates the oil pan altogether is known as a "dry sump." The dry sump is ideal since it uses a physically separate, dedicated tank that holds a much larger volume of oil.



Return to the top of the page
Oil Pressure Switch

An oil pressure switch is switch containing a diaphragm that threads into an oil passage. When the engine oil pressure gets below a specified point, the diaphragm collapses and closes the switch that will illuminate the Low Oil Pressure Warning Light.



Return to the top of the page
Oil Pump

The oil pump is located within (or attached directly to) the engine. It picks up stored oil from within the crankcase and, with sufficient pressure, circulates it throughout the engine to provide lubrication. Some oil pumps are driven by gears, some by chains, and others are coupled directly to the crankshaft. The oil pump and its function are critical to the longevity of the engine.



Return to the top of the page
Oil Pump Gasket

On engines where the oil pump is mounted externally to the engine block, a seal/gasket is required at the mounting. The oil pump gasket can be the traditional composite type, an elastic O-ring design, or the increasingly common silicone-type sealant that is applied during engine assembly. The oil pump gasket prevents engine oil leaks when the oil is compressed.



Return to the top of the page
Oil Seal

An oil seal is typically a round neoprene rubber ring that is encased or surrounded by a metal lip whose purpose is to prevent oil from leaking past a rotating shaft.



Return to the top of the page
Oil Sludge

Oil sludge is a solid gel like substance that is created in motor oil when that oil isn't changed on a frequent basis. It is usually caused by water and dirt binding with old and broken down oil molecules and can ruin an engine.



Return to the top of the page
PCV Hose

PCV or Positive Crankcase Ventilation hose is an oil vapour carrying hose that is oil and fuel resistant and connects sections of the PCV System to another.



Return to the top of the page
PCV Valve

The positive crankcase ventilation valve (PCV valve) is a one-way valve in pollution-control equipment. It ensures that gases are evacuated continually. By venting the gases back into the intake in a controlled manner, the PCV valve controls the pressure in the crankcase caused by accumulated combustion gases.



Return to the top of the page
Positive Crankcase Pressure

Positive crankcase pressure is the pressure created in the engine oil crankcase by combustion gases leaking past the piston sealing rings, usually during hard acceleration.



Return to the top of the page
Radiator

By transferring engine heat into the airflow around the vehicle, the radiator controls the engine temperature. The radiator is of lightweight construction, using copper, brass, aluminium, or aluminium with plastic elements. The radiator has a tank on each end.

Hot coolant enters one end of the radiator and circulates through a matrix of very thin tubes that are interconnected with a honeycomb core of thin, foil-like metal strips. As the hot coolant travels across the radiator core, heat is radiated into the air flowing through the radiator's honeycomb-like core. The coolant exits the radiator after giving up its "thermal load" to the surrounding air. Strategically located to optimize natural air flow, the radiator also incorporates dedicated fans to increase airflow through the radiator, further enhancing its efficiency.



Return to the top of the page
Radiator Cap

The radiator cap is more than a simple cap. Applying the laws of physics, the radiator cap design provides a means of increasing the boiling point—and thus the efficiency—of the coolant mixture. By positively sealing the cooling system, the boiling point will increase as the pressure within the cooling system increases. The cap functions as a control or relief valve, maintaining pressure by venting the pressure off at the right time (typically 14 to 18 psi). This prevents the coolant from boiling when carrying more heat.

The second function of the radiator cap comes into play when the vehicle is shut off. As the coolant temperature returns to normal, the rapid drop in temperature will create an undesirable negative pressure throughout the cooling system; the cap vents, permitting atmospheric pressure to enter the cooling system, thus equalizing the pressure.

Be very cautious when removing the radiator cap. Don't remove the cap when the engine is hot.



Return to the top of the page
Serpentine Belt

The crankshaft drives the flat, multi-ribbed serpentine belt to power engine accessories such as the alternator, air conditioning compressor, power steering pump, and sometimes the water pump. The serpentine belt is a modern, more efficient replacement for the earlier "V" belt design. The name serpentine describes the path of the flexible belt—it goes over and around multiple pulleys. This belt has its own tension and requires regular inspection and maintenance.



Return to the top of the page
Spark Plug

Spark plugs are installed in the engine cylinder head and located with the spark plug electrodes or tip within the combustion chamber. Engines may have one or two spark plugs per cylinder and each spark plug can have from one to four electrodes. When an appropriately-timed electric spark occurs at the spark plug electrode, ignition occurs within the combustion chamber. Spark plug types are specific to each vehicle and should be replaced according to the manufacturer's specifications.

Mechanics' Corner: More Technical Detail

The spark plug is a metal and ceramic device that is threaded directly into each cylinder's combustion chamber. There are two electrodes on each spark plug. The centre electrode is connected to the spark plug wire that runs from the cap of the distributor. This centre electrode is insulated by ceramic material from the ground electrode. The ground electrode is on the outer edge of the spark plug and is part of the threads that screw directly into the cylinder head. There is a gap between the centre and ground electrode (usually about the width of a penny) that the high voltage jumps across, which creates an arc of electricity similar to a lightning bolt. This ignites the compressed mixture of air and fuel inside the combustion chamber that pushes down on the piston as it burns and expands.



Return to the top of the page
Supercharger

A supercharger is a mechanically driven air compressor that forces air into the induction system of an internal combustion engine (forced induction). This is to provide more oxygen to the cylinders for increased power from the combustion process.



Return to the top of the page
Thermostat

The thermostat maintains the operating temperature of the engine (approximately 180 to 200 degrees) by regulating the flow of coolant through the engine.



Return to the top of the page
Thermostat Gasket

A gasket is a mechanical seal that fills the space between two objects, creating a seal at the interface. The thermostat gasket prevents the leakage of coolant between the thermostat housing and the engine.



Return to the top of the page
Timing Belt

The timing belt is a toothed belt that replaces the timing chain and timing gears used in earlier designs. The timing belt is used to drive the camshaft via the crankshaft. Because of its toothed design, the timing belt maintains synchronization ("timing") between the crankshaft and camshaft. The timing belt requires no lubrication.



Return to the top of the page
Timing Belt Idler

The timing belt idler is a bearing similar in size and shape to a roller skate wheel. It is positioned in contact with the timing belt, which helps to stabilize it. Some engines with longer belt paths (such as V8s) use multiple timing belt idlers.



Return to the top of the page
Timing Belt Pulley

The timing belt pulley is a toothed sprocket that is mounted on the front of the crankshaft and drives the timing belt.



Return to the top of the page
Timing Belt Tensioner

In order to eliminate slack, the timing belt tensioner puts pressure on the timing belt.

Correct timing belt tension is critical to the longevity and performance of the timing belt. Most vehicles use a timing belt idler on an eccentric pivot to set the tension during belt installation, sometimes in conjunction with a hydraulic damper. Some vehicles use a calibrated spring to provide initial belt tension during assembly.



Return to the top of the page
Timing Chain

The timing chain keeps internal engine components in sync with each other by causing valves to open and close at the proper time. On many engines, the crankshaft drives the camshaft via a timing chain, in much the same fashion as pedals drive a bicycle wheel via a chain.



Return to the top of the page
Timing Chain Cassette

A timing chain cassette is a set of two timing gear sprockets connected by a timing chain and sold as a set.



Return to the top of the page
Timing Chain Tensioner

The timing chain tensioner puts pressure on the timing chain to eliminate slack.



Return to the top of the page
Timing Cover

A timing cover is a cast or machined metal (and sometimes plastic) enclosure whose purpose is to cover and protect the timing gears, chain or belt from dirt, dust and debris.



Return to the top of the page
Timing Cover Gasket

Vehicles with timing chains or timing gears require oil for these components, which is stored in the area by the timing cover. To ensure a tight seal, a timing cover gasket or O-ring style seal is installed between the timing cover and the engine block. Some engines use a simple silicone-type sealant that is applied during engine assembly.



Return to the top of the page
Turbo Hose

A turbo hose is a large diameter neoprene or silicone rubber hose that connects the air induction components of a turbocharger system.



Return to the top of the page
Turbocharger

A turbocharger is an exhaust gas driven air compressor that forces air into the induction system of an internal combustion engine. This is to provide more oxygen to the cylinders for increased power from the combustion process.



Return to the top of the page
Upper Intake Manifold

An upper intake manifold is a plenum, or air holding enclosure, that connects the throttle body to the lower intake manifold which contains the injectors mounted in the runners and ports that go to the individual cylinders. It allows for a substantial body of intake air to be readily available which enables improved acceleration response. This part is sometimes called the upper intake plenum or upper intake clamshell.



Return to the top of the page
Upper Radiator Hose

An engine has two radiator hoses—lower and upper. The upper hose carries hot coolant from the engine back to the radiator to be re-cooled. The lower hose brings coolant (a mixture of water and antifreeze) that has been cooled in the radiator to the engine, where it circulates and absorbs heat. The radiator hoses are located between the radiator and the engine block.

Radiator hoses are made from rubber and will deteriorate over time. Periodically check for cracks, damage, swelling, or contamination due to oil leaks. Some manufacturers specify replacement intervals for radiator hoses.



Return to the top of the page
Valve Cover

A valve cover is a cast and/or machined metal (and sometimes plastic) enclosure whose purpose is to cover and protect the components of the valve train and camshaft(s) from dirt and debris and to contain its lubricating oil.



Return to the top of the page
Valve Cover Gasket Set

The valve train at the cylinder head requires a constant flow of oil; the function of the valve cover is to contain this oil supply. Valve cover gaskets can be a composite type, an O-ring design, or a silicone-type sealant that is applied during engine assembly. The gasket set fills the gaps between the cover and the valve.



Return to the top of the page
Valve Cover Seals

Valve cover seals cover the valve train to prevent engine oil leaks; they act as a gasket between the valve cover and the cylinder head.



Return to the top of the page
VGT Solenoid

A VGT or Variable Geometry Turbo Solenoid is an electronic actuator that changes the vane angle in a variable geometry turbocharger, which allows for more boost at lower engine speeds. The purpose of a variable geometry turbo (VGT) is to provide better low speed power and acceleration and decrease the apparent turbo 'lag'.



Return to the top of the page
Water Pump

The water pump pushes coolant through a vehicle's cooling system. When the thermostat opens, the water pump circulates coolant to the radiator, where it is cooled. It is then drawn back into the engine, where it circulates and absorbs heat.

The rotating water pump can be driven independently via its own belt or run with the existing serpentine belt. Current designs use the timing belt to drive the water pump; therefore, you should replace the water pump in conjunction with scheduled timing belt replacement.



Return to the top of the page
Water Pump Gasket

The water pump requires a gasket at its mounting point to the engine. This gasket can be the traditional composite type, an elastic O-ring design, or the increasingly common silicone-type sealant that is applied during engine assembly


EXHAUST AND EMISSIONS



Return to the top of the page
Evaporative Control (EVAP) System

The evaporative control (EVAP) system captures any raw fuel evaporating from the fuel storage system (e.g. the fuel tank, the filler neck, and fuel cap). Under precise operating conditions dictated by engine temperature, speed, and load, the EVAP system stores and purges these captured fuel vapours back into the combustion process.



Return to the top of the page
Exhaust and Emissions

Exhaust systems reduce the amount of noise produced by the engine and channel the high-temperature, poisonous exhaust gases from the engine by safely routing them under the vehicle. Then, through a system of manifolds, pipes, and sound-absorbing mufflers, the gases are released out of the back of the vehicle.

Emission control systems reduce the amount of harmful gases and particles released by vehicle operation. These systems have evolved into complex computer-controlled systems that balance ever-tightening vehicle pollution control regulation by the U.S. government with the constant demand for more power and economy from vehicle owners.

Related Services & Repairs:
######Catalytic Converter
######EGR Valve
######Exhaust Manifold
######Exhaust Pipe
######Muffler
######Oxygen Sensor
######PCV Valve

Tailpipe When an engine operates, it burns fuel. Because no engine can burn 100 percent of the fuel, harmful gas and particulate by products (emissions) are released.

The Clean Air Act Extension in 1970 mandated that the Environmental Protection Agency (EPA) "develop and enforce regulations to protect the public against airborne contaminants that are known to be hazardous to human health." The EPA found that motor vehicles produced three main types of harmful gases and particulates:

Hydrocarbons (HCs)
Raw, unburnt fuel particles from the combustion process that are suspended in the exhaust gases or released in a raw state from the fuel storage and crankcase systems.

Carbon monoxide (CO)
A fuel and oxygen gas formed from incomplete combustion.

Nitrogen oxide (NOx)
A nitrogen and oxygen gas compound that is formed when combustion temperatures go above 2500° F.

In conjunction with the EPA, vehicle manufacturers from around the world developed vehicle emission control systems and devices to control (and in some cases eliminate) the production of these harmful emissions. Vehicle emission control systems use a two-tiered approach in the management of these harmful substances.

Upstream Emissions Control
Manages the pre-combustion and combustion process and recycles leaked fuel storage vapours and crankcase vapours into the combustion flow.

Downstream Emissions Control
Monitors the results of the combustion process by constantly testing the oxygen content in the exhaust system before and after the catalytic converter. This information is fed to the engine management computer, which adjusts the combustion process, thereby completing a "closed loop."

The catalytic converter provides a means to "after burn" the three remaining harmful substances (HCs, CO, NOx) and converts them back into the non-poisonous substances of carbon dioxide (CO2), oxygen (02), and water (H20). Some vehicles deploy the use of a secondary air injection system to provide the extra oxygen needed at critical times to complete the combustion process. This secondary air is injected into the exhaust manifold(s) and/or catalytic converter(s) by a computer-controlled electric pump or pulse valve(s) and is distributed by specialized plumbing and check valves.

Common Upstream Emission Control Systems:

* Positive Crankcase Ventilation (PCV) System
* Evaporative Control (EVAP) System
* Exhaust Gas Recirculation System
* Fuel Management System
* Spark Control System
* Variable Valve Timing System
* The cooling system and thermostat have recently been included in the upstream emission controls.

The cooling system provides accelerated engine warm up by restricting the amount of coolant flow. The cooling system also provides an ever-narrowing window of allowable operating temperature by utilizing more advanced thermostat design and computer-controlled, speed-varied cooling fan(s) operation. This allows the engine to reach and maintain optimal air-to-fuel burning temperature as quickly as possible, thereby minimizing the "dirty" warm up emissions output and maximizing overall fuel economy. A cold (or cool) engine needs a wasteful "rich" air-to-fuel mixture in order to operate and compared to a properly warmed-up engine, its combustion only burns a fraction of this "rich" mixture. An engine that runs too hot will produce nitrogen oxide (NOx) and will misfire, which produces hydrocarbons (HCs) and NOx. The cooling system controls maintain the ideal engine temperature range of 195 to 205°F.

* The comprehensive component monitor is a software program inside the engine management computer that continually monitors the performance of the upstream emission control sensors and actuators. It constantly compares the sensor readings to each other in order to verify that the readings are within "rational" tolerances (e.g. is the intake air temperature sensor within a "rational" range of the engine coolant temperature sensor?). If it is not, then an emissions code will be set and the Check Engine Light will illuminate. The comprehensive component monitor also allows for adaption of the range (within preset limits) of the sensor readings to account for engine and component wear. This adaption is then shared with the other upstream emission systems, which modify their operating parameters to account for engine and component wear.

Downstream Emissions Control Systems:

* The exhaust manifold is the first downstream emission control device.

* The catalytic converter is a sophisticated after-burning device designed to complete the combustion of the exhaust gases that pass through it.

* The secondary air system adds oxygen to the exhaust gases under specific operating conditions to aid in the final "burn off" of the emissions.

* The oxygen sensor is a device that constantly monitors the oxygen content in the exhaust gases and sends this information back to the engine management computer (ten or more times per second).

Emissions systems also gave birth to fuel injection, which is now found on virtually every modern vehicle. It increases engine efficiency by injecting precise amounts of fuel in a fine mist spray for optimal combustion. This greatly reduces unburnt fuel (hydrocarbons) emissions and reduces the amount of fuel required.



Return to the top of the page
Exhaust Gas Recirculation (EGR) System

The exhaust gas recirculation (EGR) system recycles a small amount of exhaust gas from the exhaust system (usually no more than 10 percent) and mixes it with the intake manifold air going into the combustion chambers. The addition of this inert (or non-combustible) exhaust gas limits the peak combustion temperatures to a range that is below 2500° F, where the formation of nitrogen oxide (NOx) is known to occur.



Return to the top of the page
Fuel Management System

The fuel management system is a computer-controlled group of sensors and actuators that work together to precisely measure the amount of air entering the engine. The system then calculates the optimum amount of fuel needed to provide the best power from combustion while still keeping the exhaust emissions well within the EPA-mandated guidelines.



Return to the top of the page
OBD Code P0171 and P0174

This is intended to provide basic information about the P0171 and P0174 fault codes, what can and cannot cause it to occur, but also includes technical information for a better understanding of this code as well as the diagnostic procedures involved. This information is from our emissions expert and we suggest taking this to the shop if they are having problems diagnosing this code.

Related Information

* Check Engine Light
* Emission Gas Definitions
* Intake Manifold Gasket
* Mass Airflow Sensor
* Fuel Filter Replacement
* Fuel Pump Replacement

OBD II Fault Code:

* P0171 Fuel System Too Lean (Bank 1)
* P0174 P0174 Fuel System Too Lean (Bank 2)

Symptoms:

Check Engine Light will be illuminated
In some cases no adverse conditions may be noticed by the driver
In other cases there may be performance problems, such as a lack of power on acceleration and even some ‘coughing’ or misfiring. The vehicle may have trouble idling, especially when
cold or when sitting at a stoplight

Common Problems:

* Vacuum Leaks (Intake Manifold Gaskets, vacuum hoses, PCV hoses etc.)
* Mass Airflow Sensor (MAF)
* Plugged Fuel Filter or weak Fuel Pump
* Plugged or dirty Fuel Injectors

Common Misdiagnosis:

* Oxygen Sensors

Polluting Gases Expelled:

* NOX – Oxides of Nitrogen -> toxic gases that adversely affect breathing and colour the sky
* HC’S –Hydrocarbons -> unburned droplets of raw fuel that smell, effect breathing and colour the sky

The Basics:

Combustion engines operate by burning an air/fuel mixture of about 14.7/1 (14.7 parts air/1 part fuel). When the air ratio goes above 14.7 parts, this is called a “lean” mixture, and if the air drops below 14.7 parts it is called a “rich” mixture.

Lean Mixture = Too much air, not enough fuel
Rich Mixture = Too much fuel, not enough air

To keep the engine running properly within this 14.7/1 mixture, the Engine Control Module measures the oxygen content in the exhaust with “Oxygen Sensors” and makes adjustments to the mixture by injecting more or less fuel with the fuel injectors.

The control module operates within specific parameters, and under normal conditions it will make minor adjustments to the air/fuel mixture. When these adjustments become too large a fault code is set. In this situation (P0171, P0174) the oxygen sensors are detecting too much oxygen in the exhaust and the control module is adding more fuel than normal to sustain the proper air/fuel mixture. (Lean Condition)

P0171-P0174 Diagnostic Theory for Shops and Technicians:

When a vehicle has the fault code P0171 and or P0174, it means that the automatic mixture adjustment that is made by the computer is at its maximum. Code P0171 is described as "Fuel System Too Lean Bank 1" where as Code P0174 is "Fuel System Too Lean Bank 2". Code P0174 mainly applies to V6 or V8 engines because 4 cylinder engines generally have 1 bank. There are a few exceptions. Some of the high performance 4 cylinder and straight 6 cylinders engines split the cylinders into groups of 2 or 3 and call them separate banks, such as Subaru, BMW or Lexus.

When the code says that the Fuel System is "Too Lean", it means that the computer has been adjusting the fuel mixture richer and adding more and more fuel. This is called Long Term Fuel Trim. Ideally, the Long Term Fuel Trim should be close to 1-2%. When a code P0171 is flagged, it means that the Fuel Trim is anywhere from 15% to as high as 35% compensated. When this happens, the computer knows that there is an irrational condition in the control of the Fuel System. The first step in the diagnosis of a code P0171 and/or P0174 is to look at a minimum of 3 ranges of the Long Term Fuel Trim numbers on a scanner. Check the idle reading, 3000 rpm unloaded and 3000 rpm with at least 50% load. Then check the freeze frame information for the code to see which range(s) failed and what the operating conditions were. Before we get into the main causes of P0171, let’s explore why this code matters.

Why should we care if the Fuel System is too lean? And why this should be addressed!

Lean running cars and light trucks are highly polluting vehicles. Most of the NOx pollution is caused by the vehicles that are running too lean. NOx is very poisonous, brings on Asthma and causes the sky to turn that putrid yellow colour. A lean running car also begins to misfire which puts raw fuel or HC's into the atmosphere which are also very poisonous and colour the sky. When you are behind a car or truck and it smells very bad and makes your eyes burn, it is misfiring and running too lean. A rich running engine has no smell ( CO is odourless ) and the only thing you may smell is a little of that rotten egg smell from the sulphur being burned by the Catalytic Converter in the extremely rich cases like when you are behind a big SUV at full throttle going up a long steep hill.

P0171 is NOT an Oxygen Sensor Problem. In order for the code P0171 to set, the Oxygen Sensors had to have passed their readiness tests and not set any pending or persistent codes. This means that the computer has run a series of tests to validate the data that is received from the Oxygen Sensors. Then it looks at the Fuel Trim adjustment.

So, what are some common causes for P0171?

A vacuum leak is very common. It could be a torn PCV hose, a torn Intake Air Boot, or even a broken seal on the dipstick because, the dipstick is a part of the PCV system and if it does not seal, too much unmetered air (air the computer can’t measure or ‘meter’) will enter the engine. Don’t rule out a sticking/leaking EGR Valve or leaking EGR or Intake Manifold Gasket. If it is a V6 or V8 engine and the code is only on 1 side (Bank), it could very well be a defective Intake Manifold Gasket or cracked/leaking manifold.

What about when there is a code P0171 and there is no vacuum leak found or both code P0171 and P0174 set?

A Mass Air Flow Sensor that is ‘under reporting’ to the computer can be a common cause of a code P0171 or on a V engine codes P0171 and P0174. Basically what this means is that the Air Flow Sensor is telling the computer that much less air is entering the engine than the actual amount. This causes confusion between the Oxygen Sensors that tell the computer that more and more fuel is needed. The computer gets confused, because it sees the measurement from the Air Flow Meter or Sensor and then it hears the Oxygen Sensor complain that the mixture is still too lean. The computer keeps trying to compensate until it gets ‘confused’ and sets the code. It is important to re-state that the Oxygen Sensors are telling the TRUTH! The Fuel Mixture is too lean. In this case the Air Flow Meter or Sensor is not doing its job of reporting the real amount of air entering the engine.

* There is a very effective ‘truth test’ for any Mass Air Flow Sensor. Start the engine and let it idle and then check the Barometric Pressure reading on the scan tool data. If the reading is say 26.5 and you are close to sea level, you know that you have a defective Air Flow Meter because it is telling you that you are at about 4500 ft above sea level. You can find conversion tables for these reading on the Web. The Barometric Pressure Sensor is part of the Mass Air Flow Sensor and will cause the Mass Air Flow Sensor to send incorrect data to the engine control module. Sometimes the Air Flow Sensor gets dirty and the sensing wire gets covered with dust or oil residue. This can also cause a P0171. Cleaning the sensor often works for a while but eventually the MAF sensor needs to be replaced. Always make sure the Air Filter and Air Filter enclosure is dirt and dust free. Clean and replace as needed or the new MAF will fail in a short amount of time.

Some of the other causes of P0171, but less common are a plugged fuel filter or poorly functioning Fuel Pump. The computer hears, truthfully, from the Oxygen Sensor that the Fuel Mixture is too lean and the computer keeps increasing the amount of fuel being delivered into the combustion chambers but in this case, the Fuel System can’t increase the amount of fuel. Be sure to check and verify that fuel pressure and delivery are at spec if the above inspections do not reveal any problems. If fuel pressure and volume are good scope the injectors and if needed perform injector drop and or flow tests to see if they are capable of delivering enough fuel. Dirty/contaminated gas can definitely plug injectors and trigger these lean codes.



Return to the top of the page
OBD Code P0401

This is intended to provide basic information about the P0401 fault code, what can and cannot cause it to occur, but also includes technical information for a better understanding of this code as well as the diagnostic procedures involved. This information is from our emissions expert and we suggest taking this to the shop if they are having problems diagnosing this code.

Related Information:

* Check Engine Light
* Emission Gas Definitions
* MAP Sensor
* EGR Valve Replacement

OBD II Fault Code:

* P0401

Fault Code Definition:

* Insufficient EGR flow

Symptoms:

* Check Engine Light will be illuminated.
* In some cases there may be no adverse conditions noticed by the driver.
* In other cases there may be performance problems, such as pinging on acceleration, when the engine is under load or when driving the vehicle at higher speeds.

Common Problems that Trigger the P0401 code:

* Restriction in the EGR passages, usually caused by carbon build up.

* Lack of proper vacuum or electrical signal to the EGR valve.

* Lack of proper EGR system feedback to the computer from the:
Manifold Absolute Pressure Sensor (MAP)
Differential EGR Pressure Feedback Sensor (DPFE)
EGR Valve Position Sensor (EVP)
EGR Temperature Sensor

* The EGR Valve is defective.

The Basics:

NOx gases are formed when the combustion temperature is too high (2500°F) EGR Systems are used to reduce the combustion temperature, thus reducing NOx formation.

The exhaust gas recirculation (EGR) system recycles a small amount of exhaust gas from the exhaust system (usually no more than 10 percent) and mixes it with the intake manifold air entering into the combustion chambers. The addition of this inert (or non-combustible) exhaust gas limits the peak combustion temperatures to a range that is below 2500° F, where the formation of nitrogen oxide (NOx) is known to occur. In some cases where the engine is pinging and/or knocking badly from a severe lack of EGR flow, misfires can take place which allow raw Hydrocarbons (HC) to be released from the tailpipe.

P0401 Diagnostic Theory for Shops and Technicians
When the computer sets a code P0401, it means that the EGR flow monitoring criteria has not been met. The EGR monitoring criteria are a set of test values and are usually run during at least 2 different driving conditions such as steady speed freeway driving and steady speed city driving.

The engine control module determines proper EGR flow in many ways:

* temperature increase in the EGR passages when the EGR is supposed to be flowing.

* measurable amount of Manifold Pressure change when the EGR is supposed to be flowing.
* measurable change (usually a decrease) in the front Oxygen Sensor Signal.

* position change in the EGR valve as measured by an EGR Valve Position Sensor.

* amount of Spark Knock as measured by the Knock Sensor.

* amount of decrease in exhaust back pressure as measured by the Digital EGR Pressure Feedback Sensor.

The code P0401 is usually NOT a problem with the EGR valve itself. It means that the EGR system is NOT allowing enough EGR to flow back in to the combustion process to sufficiently cool the peak firing temperatures. Once the code P401 has been retrieved with a scan tool the Freeze Frame data should be documented and analyzed. This is to determine what engine conditions were present when the code was triggered. It is recommended that the vehicle be driven in such a way as to duplicate the code setting conditions with a data streaming scan tool connected, so the behaviour of the EGR operating components and feedback sensors can be monitored.

There are several tests for EGR systems to isolate whether it is an EGR control problem, a plugged or restricted system or a defective feedback device.

Here are some of the most common:

* Does the engine die when the EGR valve is manually raised to its maximum?
(Either with a vacuum pump or with a bi-directional scan tool when it’s a digital EGR valve)

* Is the EGR valve getting sufficient vacuum? (use the manufacturer EGR vacuum spec)

* Is the EGR system restricted? (The engine stumbles but does not die)

* Is the EGR system plugged? (engine RPM does not change)

* Does the EGR valve work?

* Raise the RPM to 3000 and check manifold vacuum, then open the EGR valve to its maximum and the manifold vacuum should drop by at least 3"of mercury. If it does not, there is a flow and/or restriction problem. Also do this test and verify that the MAP sensor change is proportional to the change in vacuum.

* Test the EGR temperature sensor (if equipped) with a propane torch and an DVOM.

* Test the accuracy of the EGR valve position sensor with a scan tool or DVOM by raising or lowering the EGR valve.

* Test the Digital EGR Pressure Feedback Sensor (DPFE) with a data streaming scan tool and verify that the voltage or lift percentage changes according to spec.

* Verify that the front Oxygen Sensor readings drop and that Short Term Fuel Trim increases when the EGR valve opens. (EGR leans out the mixture)

Note: if the NOx goes DOWN when the EGR valve is raised ( this test is most commonly performed on a Dynamometer ) this usually indicates that 1 or more EGR passages to 1 or more cylinders are plugged or very restricted and all of the EGR is going to 1 or 2 cylinders. When this occurs you may notice misfires and even have misfire codes with the P0401. This can occur on some Honda vehicles as well as other vehicles that use EGR ‘runners’ for each cylinder.



Return to the top of the page
OBD Code P0402

This is intended to provide basic information about the P0402 fault code, what can and cannot cause it to occur, but also includes technical information for a better understanding of this code as well as the diagnostic procedures involved. This information is from our emissions expert and we suggest taking this to the shop if they are having problems diagnosing this code.

Related Information:

* Check Engine Light
* Emission Gas Definitions
* EGR Valve Replacement
* MAP Sensor Replacement

OBD II Fault Code:

* P0402

Fault Code Definition:

* Excessive EGR flow

Symptoms:

* Check Engine Light will be illuminated

* In some cases there may be no adverse conditions noticed by the driver

* In other cases there may be performance problems, such as dying at stop signs or rough idling, hesitation, misfires or lack of power, especially during acceleration and a decrease in fuel economy

Common Problems that Trigger the P0402 code:

* Excessive Vacuum signal or Electrical signal to the EGR valve
* Lack of proper EGR system feedback to the computer from the:
o Manifold Absolute Pressure Sensor (MAP)
o Differential EGR Pressure Feedback Sensor (DPFE)
o EGR Valve Position Sensor (EVP)
o EGR Temperature Sensor
* The EGR Valve is defective and is opening too far, or not properly closing

* Common Misdiagnosis
* Ignition System
* Fuel System
* Oxygen Sensor
* EGR Valve

Polluting Gases Expelled:

HC’S – Hydrocarbons -> unburned droplets of raw fuel that smell, effect breathing and colour the sky
CO – Carbon Monoxide -> partially burned fuel that is an odourless, poisonous gas

The Basics:
NOx gases are formed when the combustion temperature is too high (2500°F) EGR Systems are used to reduce the combustion temperature, thus reducing NOx formation.

The exhaust gas recirculation (EGR) system recycles a small amount of exhaust gas from the exhaust system (usually no more than 10 percent) and mixes it with the intake manifold air entering into the combustion chambers. The addition of this inert (or non-combustible) exhaust gas limits the peak combustion temperatures to a range that is below 2500° F, where the formation of nitrogen oxide (NOx) is known to occur. In some cases where the engine is pinging and/or knocking badly from a severe lack of EGR flow, misfires can take place which allow raw Hydrocarbons (HC) to be released from the tailpipe.

When the computer sets a code P0402, it means that the EGR flow monitoring criteria has not been met. The EGR monitoring criteria are a set of test values and are usually run during at least 2 different driving conditions such as steady speed freeway driving and steady speed city driving.

The test criteria during EGR operation include:

* temperatures reached in the EGR system.

* Intake Manifold Pressure change.

* amount of change (usually a decrease) in the front Oxygen Sensor(s) Signal.

* amount of position change in the EGR valve as measured by an EGR Valve Position Sensor.

* amount of Spark Knock as measured by the Knock Sensor.

* amount of decrease in exhaust back pressure as measured by the Digital EGR Pressure Feedback Sensor.

Code P0402 is often set when the EGR monitoring criteria are excessively triggered, such as too much Manifold Pressure change, too much Oxygen sensor change, too much EGR Temperature change etc. Code P0402 is often set when the EGR monitoring sensors are still showing EGR flow after the EGR monitoring tests are complete.

P0402 Diagnostic Theory for Shops and Technicians

The code P0402 is usually NOT a problem with the EGR valve itself. It means that the EGR system is NOT allowing enough exhaust gases to flow back in to the combustion process to sufficiently cool the peak firing temperatures. Once the code P0402 has been retrieved with a scan tool the Freeze Frame data should be documented and analyzed. This is to determine what engine conditions were present when the code was triggered. It is recommended that the vehicle be driven in such a way as to duplicate the code setting conditions with a data streaming scan tool connected, so the behaviour of the EGR actuating components and feedback sensors can be monitored.
There are several tests for EGR systems to isolate whether it is an EGR control problem, an EGR feedback sensor problem or a defective/sticking EGR valve.

There are several tests for EGR systems to isolate whether it is an EGR control problem, an EGR feedback sensor problem or a defective/sticking EGR valve. Here are some of the most common:

* Raise the engine rpm to about 2000, raise the EGR valve to its maximum position and then let it suddenly snap back to a closed position. If the idle becomes smoother, then this could mean that the EGR valve could be sticking open at times.
(Use either a vacuum pump or bi-directional scan tool if it’s a digital EGR valve)

* Is the EGR valve getting vacuum when it shouldn’t, such as during idle?

* Check the EGR valve for smooth operation throughout its range of motion. (either vacuum or digital)

* Test the accuracy of the EGR valve position sensor with a scan tool or DVOM by raising and lowering the EGR valve. Does it show the proper open/closed voltage or percentage?

* Test the Digital EGR Pressure Feedback Sensor (DPFE) with a data streaming scan tool and verify that the amount of exhaust backpressure voltage or percentage changes according to spec.

* Verify that the front Oxygen Sensor readings drop and that Short Term Fuel Trim increases when the EGR valve opens and then returns to normal when the valve is closed. Short Term Fuel Trim should increase when the valve opens and should decrease when the valve closes properly.

* Disconnect the EGR valve (either vacuum or electrical type) and test drive the vehicle. Is there any noticeable change or improvement in the vehicle performance?

Note: Some EGR systems use 2 vacuum solenoids to supply and bleed vacuum to the valve. If either the supply vacuum solenoid or bleed solenoid malfunction, then the valve will be open at times when it should not be, thus causing a code P0402. Some Toyotas as well as some other vehicles use this type of dual vacuum solenoid EGR control.

Note: Some digital EGR valves can get a piece of carbon stuck in between the pintle shaped tip of the valve and its seat, thus causing EGR flow during incorrect driving conditions. This condition may not set an EGR code, but may set misfire codes or rich running codes. One way to test for this condition is to test drive the vehicle with a data streaming scanner and study the EGR Position Sensor readings. They should go to 0% at idle, if not, there may be an obstruction in the valve, but the reading is often not far enough off to set an EGR code. I have seen this on GM, Honda and Acura vehicles, but it can happen on any of the Digital EGR equipped vehicles.



Return to the top of the page
OBD Code P0420

This is intended to provide basic information about the P0420 fault code, what can and cannot cause it to occur, but also includes technical information for a better understanding of this code as well as the diagnostic procedures involved. This information is from our emissions expert and we suggest taking this to the shop if they are having problems diagnosing this code.

Related Information

Check Engine Light
Emission Gas Definitions
Front Oxygen Sensor Repl.
Rear Oxygen Sensor Repl.
Catalytic Converter Repl.
Ignition Wire Replacement
Cap/Rotor Replacement
Spark Plug Replacement

OBD II Fault Code:
P0420

Fault Code Definition:
Catalyst System Efficiency below threshold

Symptoms:
Check Engine Light
In most cases there are no adverse conditions noticed by the driver
In some cases there may be some performance problems noticed by the driver such as a lack of power from a restricted and/or damaged Catalytic Converter

Common Problems that Trigger the P0420 code:
Inefficient Catalytic Converter(s)
Defective Front or Rear Oxygen Sensor(s)
Misfiring engines can also lead to a P0420 code

Common Misdiagnosis:
Oxygen Sensors

Polluting Gases Expelled:
NOX – Oxides of Nitrogen -> toxic gases adversely affect breathing and colour the sky
HC’S –Hydrocarbons -> unburned droplets of raw fuel that smell, effect breathing and colour the sky
CO - Carbon Monoxide -> partially burned fuel that is an odourless but deadly poisonous gas

Note: Very recently, Volkswagen and Audi have extended their Catalytic Converter coverage to 10 years and or 100,000 miles on many of their 1999 to 2002 vehicles whenever a code P0420 occurs.


The Basics:

The catalytic converter has an appearance similar to a muffler. It is typically a stainless steel housing with a ceramic honeycomb inside that is impregnated with platinum, palladium, and rhodium. These are all rare metals which help to explain the high price of catalytic converters. These elements help clean up harmful exhaust gases that otherwise would be expelled from the tail pipe. Catalytic converters are quite efficient, but if engine maintenance is neglected or an engine is allowed to run rough, damage may occur to the catalytic converter, resulting in costly repairs. To replace the catalytic converter, the vehicle is raised to gain access to its underside. The converter is removed from the exhaust system and the new catalytic converter is installed.

Learn More:

The catalytic converter is a sophisticated after-burning device designed to complete combustion of the exhaust gases that pass through it. It is a stainless steel container with an inlet and outlet pipe that looks similar to a muffler. Inside, the catalytic converter is a ceramic monolithic structure that has honeycomb like passages running through it. This structure has several sections called beds that are thinly coated with rare metals that react with the compounds in the exhaust gases to complete the combustion process, thereby cleaning the exhaust of harmful emissions.

* The first section of the catalytic converter is called the reduction bed and is coated with rhodium. It is called the reduction bed because its purpose is to reduce the NOx gases back in to harmless nitrogen and oxygen

* The next section of the catalytic converter is the oxygen storage bed, which is coated with cerium. Its purpose is to maintain an ideal level of oxygen for use by the rear of the converter. It does this by storing and releasing the oxygen that gets released from the reduction of NOx in the previous reduction bed

* The oxygen is then available for use in the final oxidizing bed, which is coated with platinum and palladium. The purpose of the oxidizing bed is to complete the combustion of CO by adding oxygen. The oxidizing bed also uses oxygen to burn any of the raw HCs that still remain in the exhaust gases


P0420 Diagnostic Theory for Shops and Technicians

Code P0420 is set when the Catalyst monitor sees a decrease in voltage from the rear or Monitoring Oxygen Sensor(s) and an increase in switching activity from rich to lean to rich etc that closely resembles the front Oxygen Sensor(s) during the time when the computer is activating the Catalytic Converter monitor test. The voltage threshold is usually a minimum of 650 millivolts which indicates a low level of Oxygen. When the voltage goes too far below the 650 millivolt minimum, it indicates a higher level of Oxygen. This means that not all of the Oxygen is being consumed by the combustion process or by the after burning effect of the Catalytic Converter. When the Oxygen level gets too high, it means that the Cerium or Oxygen storage bed has degraded to the point where it is no longer able to store Oxygen created by the reduction of NOx (Nitrogen and Oxygen). This Oxygen is essential for the rear Oxidation bed to complete the conversion of CO into CO2 and HCs into H20 and CO2.

Here are some common tests for the diagnosis of this code:

* Retrieve the code and then write down the freeze frame information

* If there are any misfires, ignition, fuel and/or intake problems, these must be completely addressed and repaired before the Catalyst code is addressed. Any misfire, ignition and/or fuel system problem will ruin a Catalyst in short order. They are often the root cause for the Catalyst code P0420 to have set in the first place

* Test drive the vehicle at or near the freeze frame conditions to verify that the rear Catalyst Monitoring Oxygen sensor is either mirroring the front Oxygen sensor and/or is not reaching the 650 millivolt threshold during 55-60 mph cruise conditions. If either of these conditions can be easily verified, then the Catalytic Converter is defective

* If there is any doubt about the condition of the front and/or rear Oxygen sensors, then check the Mode 6 data for all the Oxygen sensor monitor tests. If any of the front or rear Oxygen sensors barely pass their Mode 6 tests, then clear any and all codes and perform a drive cycle and see how well the front and rear Oxygen sensors pass their Mode 6 tests. They need to pass the Mode 6 tests with ‘flying colours’ or they will confuse the OBD-II diagnostic software and possibly trigger a false code P0420. This is an important concept because if the front Oxygen sensor is slow and barely passes its monitor tests, it can fool the computer into thinking that the Catalyst has failed because the computer just watches how closely the switching speed of the front Oxygen sensor compares to the switching speed of the rear Monitoring Oxygen sensor. If the rear Monitoring Oxygen sensor is losing bandwidth and not able to easily reach the 650 millivolt threshold, but still passes its monitor tests, then it too can fool the computer into setting a P0420 code

* If the Catalyst has failed, be sure to check for any software updates for the power train computer. Many of the OBD-II equipped vehicles require software updates whenever the Catalyst is replaced

Note: Most vehicles need an OEM Catalyst, especially if there is a Catalyst related software update required. Hondas and Toyotas usually re-set the P0420 code unless an OEM catalyst is used as a replacement. Techs and shops ‘tear their hair out’ and replace all the Oxygen sensors etc only to find that the Honda or Toyota vehicle required an OEM Catalyst. This information is meant to prevent a huge amount of grief and customer complaints. California, as of 1/1/2009, has made it illegal to use even a ‘direct fit’ after market OBD-II Catalytic Converter because there have been so many comebacks. Presently all the aftermarket Converter companies are re-working their designs so they can be certified for use in OBD-II vehicles in California.



Return to the top of the page
OBD Code P0440

This is intended to provide basic information about the P0440 fault code, what can and cannot cause it to occur, but also includes technical information for a better understanding of this code as well as the diagnostic procedures involved. This information is from our emissions expert and we suggest taking this to the shop if they are having problems diagnosing this code.

Related Information

Check Engine Light
Emission Gas Definitions

OBD II Fault Code:
P0440

Fault Code Definition:
Evaporative System Malfunction, large leak

Symptoms:

* Check Engine Light will illuminate
* In most cases there are no adverse conditions noticed by the driver
* In some cases there may be a noticeable fuel odour caused by the release of fuel vapours


Common Problems that Trigger the P0440 code:

* Missing Fuel Cap
* Defective or damaged Fuel Cap
* Distorted or damaged Fuel Tank filler neck
* Torn or punctured Evaporative System hose(s)
* Defective Fuel Tank Sending Unit gasket or seal
* Split or damaged Carbon Canister
* Defective Evaporative Vent Valve and/or Evaporative Purge Valve
* Defective or damaged Fuel Tank
* Defective Fuel Tank Pressure Sensor

Common Misdiagnosis:

* Fuel Cap
* Evaporative Purge Valve
* Evaporative Vent Valve

Polluting Gases Expelled:
HC’S –Hydrocarbons -> unburned droplets of raw fuel that smell, effect breathing and colour the sky

The Basics:

The evaporative control (EVAP) system captures any raw fuel evaporating from the fuel storage system (e.g. the fuel tank, the filler neck, and fuel cap). Under precise operating conditions dictated by engine temperature, speed, and load, the EVAP system stores and purges these captured fuel vapours back into the combustion process.

Learn More:

The Evaporative Control System is designed to not only capture, store and purge any raw fuel vapours that leak from any areas of the Fuel Storage System but also to run a series of self-tests that confirm or deny the Operational and Vapour Holding ability of the System. This is an important task because at least 20% of the Vehicle produced Air Pollution originates from malfunctioning Vehicle Fuel Storage Systems. There are many ways for vehicles to 'leak test' the Evaporative System, but most perform the leak test either when the vehicle is sitting, say over night, or shortly after initial start up after the vehicle has been sitting over night. The Evaporative Systems operational performance is also tracked by the Power Train Computer by reading the change in the Oxygen Sensor voltages and Short Term Fuel Trim whenever the stored Vapours are released or 'purged' back into the combustion process. These values should indicate that fuel is being added to the system and that the overall mixture is getting richer. The purging process occurs when the vehicle is under acceleration, which is when most vehicles require additional fuel.


P0440 Diagnostic Theory for Shops and Technician

The Code P0440 indicates that there is a large leak in the Evaporative System, but this is somewhat misleading. What the code really indicates is that the Evaporative System will not create a significant vacuum when it performs its leak test. Let's go over a little about how the Evaporative Leak Test is performed by the Power Train Computer. When the leak test is performed, the vehicle must have been sitting for at least 4-8 hours in order for the engine temperature and air temperature to be identical. This is to provide a base line for the test because gasoline and diesel are volatile fluids that expand and vaporize easily with warm temperatures. When the Leak Test initiates, the Vapour Canister Vent Valve is closed to prevent any fresh air from entering the Evaporative System. Then the Purge Valve is opened which allows the engine to create a vacuum in the Evaporative System. After a specified time interval, which is usually about 10 seconds, the purge valve is shut off and the vacuum level in the system is measured with the Fuel Tank Pressure Sensor. Then a countdown initiates which measures the rate at which the vacuum decays in the system. If the vacuum decays faster than the specified rate or, if the desired amount of vacuum is never reached on 2 tests in a row, then the Power Train Computer will fail the Evaporative System for a large leak and set the code P0440. Now, what are some of conditions or components that will cause the Evaporative System to fail its leak tests?

Here are some common tests for the Evaporative System:

* Retrieve the code and then write down the freeze frame information to be used as a base line to test and verify any repair.

* Perform a careful and close inspection of all the visible hoses and components in the Evaporative System for any signs of damage or degradation that could cause a leak.

* Pay very close attention to the Fuel Tank Pressure readings. Does the Fuel Tank Pressure Sensor work properly? If it does not, the system will think that no vacuum is being created when, in fact there is a vacuum being created, but the Fuel Tank Pressure Sensor is unable to read it. The Fuel Tank Pressure Sensor is the primary feedback sensor that the Power Train Computer relies on for the leak test data.

* Inspect and test the Fuel Cap and inspect how well it fits onto the Fuel Tank Filler Neck. If the Cap will not seal or hold vacuum or pressure, then it can trigger the large leak code P0440.

* Verify that the Purge Valve and that the Vent Valve work properly and hold vacuum for a sustained amount of time, at least 30-60 seconds. If either one of these Valves function improperly, the system will never develop and/or hold the proper amount of vacuum.

* If all the components seem to look and function properly, then the next test to perform is a smoke machine test of the entire Evaporative System. This will usually root out any leaks that are hidden behind and/or under components of the vehicle. Pay close attention to the filler neck, the canister and the fuel tank, especially where the Fuel Pump and Fuel Level Sending unit are located and sealed. Occasionally when a Fuel Pump is replaced, the seal isn't replaced or properly installed and can cause a large leak in the system. You may have to remove the rear seats to pinpoint this type of leak.



Return to the top of the page
Positive Crankcase Ventilation (PCV) System

When the engine is operating (usually under load), the positive crankcase ventilation (PCV) system captures any oil vapour or raw hydrocarbons that may escape past the piston rings into the crankcase during combustion. The PCV system is a set of tubes, containers, and one-way PCV valves designed to capture, hold, and recycle these vapours back into the combustion process where they are burned as fuel.



Return to the top of the page
Secondary Air System

The secondary air system is designed to add oxygen to the exhaust gases to aid in the final "burn off" of the emissions. Fresh air is pumped into the exhaust by either an electrical/mechanical pump or a special one-way reed valve that utilizes the pulsing of the exhaust from the piston firings to suck the fresh air into the exhaust system. The secondary air is then injected into the exhaust manifolds, catalytic converters, or both.

Secondary air is used most commonly during the warm up cycle to help burn the rich air-to-fuel mixture needed to run a cold engine. Usually after two to three minutes, the catalytic converter is nearly at operational temperature, so the secondary air system shuts down. On some larger vehicles (e.g. trucks and SUVs), the secondary air system pumps air into exhaust manifolds during warm up and then directs the air into the catalytic converters during normal operation to help "burn off" the high fuel loads required to operate these heavy vehicles.



Return to the top of the page
Spark Control System

The spark control system is a set of computer-controlled sensors and actuators that work closely together to provide the optimal amount of spark—at precisely the right time—to burn the air-to-fuel mixture in the combustion chambers. This maximizes engine power while still keeping the exhaust emissions output well within the EPA-mandated guidelines.



Return to the top of the page
Variable Valve Timing System

The variable valve timing system shares some of the spark control sensor input to adjust the opening and closing time of the intake valves depending on engine temperature, speed, and load. This controls nitrogen oxide (NOx) formation while providing optimal performance and economy and minimizing the exhaust emissions. To further enhance fuel economy, some variable valve systems actually shut off some of the intake valves during highway cruise conditions.



Return to the top of the page
Catalytic Converter Replacement

The catalytic converter is one of the key components in a vehicle’s pollution control system. It reduces the level of harmful emissions in exhaust.

The catalytic converter looks similar to a muffler. It is typically a stainless steel housing with a ceramic honeycomb inside that is impregnated with platinum, palladium, and rhodium. These elements help clean up harmful exhaust gases that otherwise would be expelled from the tail pipe.

Catalytic converters are quite efficient, but if engine maintenance is neglected or an engine is allowed to run rough, damage may occur to the catalytic converter, resulting in costly repairs.

To replace the catalytic converter, the vehicle is raised to gain access to its underside. The converter is removed from the exhaust system and the new catalytic converter is installed.

Mechanics Corner: More Technical Detail

The catalytic converter is a sophisticated after-burning device designed to complete combustion of the exhaust gases that pass through it. It is a stainless steel container with an inlet and outlet pipe that looks similar to a muffler. Inside, the catalytic converter is a ceramic monolithic structure that has honeycomb like passages running through it. This structure has several sections called beds that are thinly coated with rare metals that react with the compounds in the exhaust gases to complete the combustion process, thereby cleaning the exhaust of the harmful emissions.

* The first section of the catalytic converter is called the reduction bed and is coated with rhodium. It is called the reduction bed because its purpose is to reduce the NOx gases back in to harmless nitrogen and oxygen.

* The next section of the catalytic converter is the oxygen storage bed, which is coated with cerium. Its purpose is to maintain an ideal level of oxygen for use by the rear of the converter. It does this by storing and releasing the oxygen that gets released from the reduction of NOx in the previous reduction bed.

* The oxygen is then available for use in the final oxidizing bed, which is coated with platinum and palladium. The purpose of the oxidizing bed is to complete the combustion of CO by adding oxygen. The oxidizing bed also uses oxygen to burn any of the raw HCs that still remain in the exhaust gases.

The inside of the catalytic converter operates at very high temperatures. It will not even begin to light off until it reaches 400-600 degrees Fahrenheit; it typically runs from 1200-1600 degrees depending upon how hard it is being worked. A rich- or dirty-running engine can make the catalytic converter work so hard that it will actually glow red. This is why there are catalytic converter–damaging misfire codes that illuminate the check engine light—and even make it steadily flash under severe misfire conditions.

A failing catalytic converter has many implications.

* It can cause the vehicle to fail an emissions test.

* It can set the check engine light.

* The insides can break apart and become very noisy; making a rattling sound that can become unbearable.

* It can be contaminated by coolant, oil, or fuel and produce an offensive smell.

* The inside can get too hot (from a poorly running engine) and melt. This restricts the gas flow, which causes the vehicle to lose some power, all of its power, or to not run at all.

Recommendations:

* Catalytic converters can be vehicle specific, especially in the high-performance lines. In many cases, however, a new OBDI (pre-1996) or OBDII (1996 and later) catalytic converter made by a quality manufacturer that meets or exceed the emissions requirements—and costs much less than the factory unit—can be welded into place.

* It is important to have a qualified emissions diagnostician inspect the vehicle to determine if and why the catalytic converter failed. In some cases, a catalytic converter becomes less and less efficient as the mileage increases—usually over 150,000 miles. But in many cases, a catalytic converter is ruined by an improperly running engine. This root cause needs to be resolved or the new catalytic converter will fail in a short time.

About this Repair: Catalytic Converter Replacement

Recommendations:

* Catalytic converters are very vehicle-specific parts. We recommend using a high-quality, new part, which in many places is required by emissions-control programs.

* It is very important to have the shop identify why the catalytic converter failed. Failure is almost always due to another problem, which if not resolved, will very quickly ruin a new catalytic converter.

Why this happens:

* A failing catalytic converter can cause a vehicle to fail emissions tests, the "Check Engine Light" to come on, and for the exhaust to have an unusual smell.

* A "restricted" catalytic converter can result in a loss of engine power.

Price range for Labour of Catalytic Converter Replacement: £0.00 - £0.00



Return to the top of the page
Exhaust Gas Recirculation Valve Replacement

The exhaust gas recirculation valve (EGR valve) recirculates combustion gases—including unburned hydrocarbons—back into the engine intake. This has the desirable effect of lowering the peak flame temperature in the combustion process, thus reducing the production of oxides of nitrogen, a major pollutant.

If the EGR valve does not open and close properly, the Check Engine Light will illuminate and a fault will be stored. Engine performance problems (e.g. poor idle quality or "pinging" under acceleration) can also occur.

To replace the EGR valve, the mechanic removes it from the intake manifold and then checks the EGR passageways in the EGR system to ensure they are clear; then, the new EGR valve is installed.

Note: Access to the EGR valve can be extremely limited on some vehicles.

Mechanics' Corner: More Technical Detail

* The exhaust gas recirculation (EGR) system recycles a small amount (usually no more than 10 percent) of exhaust gas from the exhaust system and mixes it with the intake manifold air going into the combustion chambers. Adding this inert non-combustible) exhaust gas limits the peak combustion temperatures to less than 2,500° F (when the formation of NOx is known to occur). The flow of this recycled exhaust gas is managed by either a vacuum or an electrically-controlled, pintle-shaped EGR valve. There are two ways the valve most commonly fails. First, it may stick in the open position, which causes a very rough idle (and a lack of power). The EGR valve can also fail in the closed position, which causes detonation on acceleration; if this happens, the vehicle will fail an emissions test for high NOx. In many cases, but not always, a Check Engine Light will illuminate to alert the driver of this failure.

* To replace the EGR valve, first remove it from the intake manifold, which is usually near the throttle body. To make sure the new EGR valve doesn't fail, clean all the EGR passages so the system will function properly. Always have a skilled emissions diagnostician check the EGR system before and after the repair to verify that all its other components work properly. It's always best to use factory-original EGR valves because they are tightly calibrated to match each engine configuration. Make sure that any engine codes are cleared and perform the proper drive cycle to make sure the emissions computer clears the self-testing of the new EGR valve without any errors.

About this Repair: EGR Valve Replacement

What to watch out for:

* Be sure that the shop cleans the EGR passages when the EGR valve is replaced. If the EGR system ports are not cleaned, the new valve is at risk of premature failure.

Recommendations:

* The entire EGR system should be inspected and cleaned when an EGR valve is replaced.

Why this happens:

* Problems with the EGR valve can trigger trouble codes, which will cause the "Check Engine Light" to come on. The vehicle may also fail emissions tests.

* EGR valve problems can cause vehicles to idle roughly.

Price range for Labour of Exhaust Gas Recirculation Replacement: £0.00 - £0.00



Return to the top of the page
Exhaust Manifold Replacement

Exhaust manifolds are attached to the engine. Exhaust gases are expelled from each cylinder of the engine into the manifolds, where the gases are then released through the exhaust system at the rear of the vehicle.

Exhaust manifolds are subject to extreme heat, which may cause them to warp or crack, necessitating their replacement.

Exhaust manifolds should be checked periodically to ensure they are free from cracks and that the exhaust hardware and heat shields are secure.

A cracked or warped exhaust manifold should be repaired immediately. The exhaust manifold is attached to the engine by simple studs and nuts. However, access to the attaching nuts can be very limited, sometimes requiring dedicated tools such as "S" and "U" shaped wrenches or swivelling sockets. After the manifolds attachment to the engine is removed the exhaust manifold itself must be withdrawn. Some vehicles offer no room to achieve this, in such cases the engine can be shifted in place to increase space as needed. In contrast many vehicles offer plenty of room to perform this job, making the removal and replacement of the exhaust manifold very straight forward. In either case, the manifold gaskets as well as the removed hardware, i.e. nuts, bolts, washers, and studs should always be replaced with new parts.

Mechanics Corner: More Technical Detail

* The exhaust manifold is the first downstream emission control device. The purpose of the exhaust manifold is to gather the extremely hot exhaust gases from the individual cylinders and channel them into a single header pipe while keeping them as hot as possible. Some exhaust manifolds are heavy cast-iron devices designed to store the extreme heat caused by the still-burning exhaust gases leaving the individual cylinders. This helps sustain the combustion burning process into the next downstream emission device, the catalytic converter. The exhaust manifold is bolted directly to the engine cylinder head.

* Because the exhaust manifold is subjected to such extreme heat, it has a tendency to crack or become warped. In addition, the fastening bolts and studs tend to break from the constant expansion and contraction caused by the punishing heat; this leads to exhaust leaks. In some cases, the exhaust manifold is an integral part of the catalytic converter, so they must be replaced as a unit.

* To replace the exhaust manifold, remove it from the cylinder head and disconnect it from the exhaust header pipe. It is not recommended to attempt to resurface a warped exhaust manifold because it will soon crack. Always replace all of the fasteners and gaskets when performing this repair so the new bolts will torque properly and the new gaskets will seal. Always make sure to clear any dust or debris from all the mating surfaces on the cylinder head and header pipe so the new manifold won't leak.

About this Repair: Exhaust Manifold Replacement
What to watch out for:

* We do not recommend resurfacing a warped exhaust manifold, as the manifold will be prone to cracking.

Recommendations:

* The new manifold should be replaced using new bolts and studs, and the assembly should be cleaned of any rust and carbon.

Why this happens:

* Exhaust manifolds are replaced because of leaks caused by cracks, warping, and broken or missing studs.

Price range for Labour of Exhaust Manifold Replacement: £0.00 - £0.00



Return to the top of the page
Exhaust Pipe Replacement

Exhaust pipes connect exhaust system components to one another. Exhaust pipes connect the exhaust manifold to the catalytic converter and the catalytic converter to the muffler.

The exhaust pipe routes harmful exhaust gas away from the engine, through the catalytic converter and muffler, and out the tail pipe.

Exhaust gas contains a large percentage of water vapour, which over time will rust and degrade the exhaust system. Components in the exhaust system may have detachable flanges to facilitate their replacement.

Despite the high water vapour content, exhaust also contains noxious gases. Holes in the exhaust system may allow exhaust gas to leak into the vehicle. If inhaled, these gases are harmful to people.

Mechanics' Corner: More Technical Detail

The exhaust pipe begins where the exhaust manifold ends. The first section is called the header pipe because it has a unique shape and is the "head" of the exhaust pipe system. It begins like the wide end of a funnel and can be four to five inches in diameter; it then narrows down to around two inches where it connects to the catalytic converter. The header pipe is usually short (one to three feet in length) because the extremely hot and still-burning exhaust gases must stay so as they enter the catalytic converter. It is here where they are "after burned" in the presence of specific rare metals and converted back into non-poisonous gases. Ideally, when the exhaust gas leaves the vehicle, it should only contain carbon dioxide (CO2), water (H2O), and oxygen (O2).

The next section of the exhaust system connects the catalytic converter to the mufflers and tailpipe. By this time, the high-temperature and poisonous nature of the exhaust gases have been greatly reduced. The main function of the exhaust system is to decrease noise and route the exhaust gases away from the passenger compartment toward the back of the vehicle where they are expelled.

It is important to remember that the exhaust system is part of the emissions system and therefore regulated. The exhaust manifold, header pipe, catalytic converter, mufflers, and all the connecting pipes are part of the emissions system. Even high-flow muffler systems can change the "scavenge" rate of the exhaust gas flow rate through the catalytic converter (which causes "dirty" exhaust emissions to be released). A change in the header pipe can cause the exhaust gases to be pushed too fast through the catalytic converter, which results in less efficient "scrubbing" of the emissions.

High-performance "header kits" must have federal, state, and local approval because too many of these kits alter the volumetric flow of the intake and exhaust gases by changing the "back pressure." In addition, these kits often change the critical location points of the oxygen sensors, which can alter the way the engine management system controls the fuel injection. In some cases, entire high-performance systems need to be removed because they cause the vehicle to fail emissions testing. Attempting to obtain a "dark side" or illegal emissions certification is not only expensive, but a felony in most states—for the vehicle owner and the supplier of the certification. A state highway patrolman, policeman, or city police officer can pull over and impound a vehicle if the exhaust system has been illegally modified. Only use the approved high-performance systems when modifying an exhaust system.

When replacing an exhaust component, the vehicle is usually raised on a lift where the underside of the vehicle and the exhaust system can be accessed. Whenever possible, it is better to use bolt-on components because these are designed and built to factory specifications. Welding in components is less desirable because the actual lengths in the sections of the exhaust system are altered. Welded-in components are usually generic one-size-fits-many and tend to be much less efficient in their operation. Use these as a last resort when the factory-specified component is unavailable or too costly to be practical.

Price range for Labour of Exhaust Pipe Replacement: £0.00 - £0.00



Return to the top of the page
Exhaust Tail Pipe Replacement

Exhaust gases are emitted from the engine, routed under the vehicle, and expelled at the rear of the vehicle. Exhaust gases are noxious; the exhaust tail pipe ensures that the gases exit and do not get trapped under the vehicle where they could leak into the passenger compartment, causing harm to the occupants of the vehicle.

The vehicle exhaust system should be inspected periodically for damage that could cause restriction of the exhaust, which may result in a loss of power. The exhaust system should also be periodically inspected for leaks that could become potentially harmful to occupants of the vehicle.

Mechanics Corner: More Technical Detail

There is more than one purpose for the exhaust tail pipe.

* The primary purpose is channelling the exhaust gases past the rear of the vehicle so they will not enter the passenger compartment. Even though the Emissions System works hard to convert all vehicle emissions back into safe gaseous chemicals it is never 100% effective under all running conditions.

* Another reason for the tailpipe is to tune the sound of the Exhaust System to give it the appropriate ‘note’ so to speak; a high performance sports car will have a different sound than a luxury sedan.

* The tail pipe can also be part of the styling of a vehicle. Many tail pipes are shaped and chromed to reflect the ‘image’ of the vehicle and complete the lines or styling intended by the designers, while other tail pipes are almost invisible and whose primary purpose is one of functionality.

Price range for Labour of Exhaust Tail Pipe Replacement: £0.00 - £0.00



Return to the top of the page
Front Oxygen Sensor Replacement

The oxygen sensor is a key component in the vehicle's pollution control system. The front oxygen sensor produces a signal that the fuel injection computer uses to determine if the engine requires more or less fuel to optimize fuel consumption.

Over time, oxygen sensors become "lazy," and their output signal deteriorate. An engine that burns oil or has a blown head gasket (which allows antifreeze into the exhaust system) may contribute to the failure of the sensor. Modern sensors have an electrical heating circuit built into them, which is prone to failure over time.

To replace an oxygen sensor, its electrical connection is disconnected, the sensor is removed from the exhaust system, and the new sensor is installed.

Mechanics Corner: More Technical Detail

Oxygen sensors constantly monitor the oxygen content in the exhaust gases and sends this information to the engine management computer 10 or more times per second.

The first oxygen sensors were mounted only in front of the catalytic converter, but as of 1996, an oxygen sensor is mounted before and after each catalytic converter.

* The purpose of the front oxygen sensor, which is mounted before the catalytic converter, is to measure how rich or lean the gases are as the gases exit the combustion chambers. Depending upon whether the exhaust gas is lean (high in oxygen content) or rich (low in oxygen content), the amount of fuel entering the engine is adjusted by the engine management computer to try and maintain an ideal mixture that produces the lowest emissions output from the catalytic converter.

* The purpose of the rear oxygen sensor is to monitor the oxygen content of the exhaust gases leaving the catalytic converter. This gives the emission system a way to monitor the operation and efficiency of the catalytic converters. The rear oxygen sensor checks several things in the post–catalytic converter gases. It measures the amount of oxygen, or peak threshold, in the exhaust gases and follows how fast the amount of oxygen changes. On some vehicles, the rear oxygen sensor is mounted midway in the catalytic converter to measure how efficiently the reduction bed converts NOx by checking the amount of oxygen that is released back into the exhaust flow.

With each new model year, manufacturers are adding more oxygen sensors to better manage engine operation. Some high-performance engines have an oxygen sensor for each cylinder as well as one for the rear of each catalytic converter: for an 8-cylinder engine, that can mean 10 oxygen sensors.

Replacing the front oxygen sensor varies from vehicle to vehicle. Some vehicles have only one front oxygen sensor and are as easy to replace as a single spark plug. Other vehicles have one or more oxygen sensors per bank, or group, of cylinders, and can be very difficult to access. The front oxygen sensor is usually on or near the exhaust manifold but in front of the catalytic converters. Usually, the electrical connector is first disconnected and then the sensor is unscrewed from the exhaust system. These initial steps can be rather tricky because some vehicles have oxygen sensor wiring that enters the passenger compartment, so disconnecting and removing then can take half an hour or more to complete.

The performance of any oxygen sensor deteriorates over time: the amount of the signal change, or bandwidth, as well as the speed, or frequency, of signal change decreases. The engine management computer is constantly monitoring this performance, and when the programmed envelope of acceptable oxygen sensor performance has been breached, the computer will set a fault code and illuminate the check engine light.

* In some cases, the oxygen sensor is contaminated by something in the exhaust gases, such as coolant from a leaking head gasket or oil from a worn engine. Even the wrong type of gasket sealer with silicone can contaminate, or foul, an oxygen sensor. If the sensor has any noticeable colouring from a leaking substance, the source of the substance must be located and repaired or any new oxygen sensor will be ruined in short order.

* Another common reason for oxygen sensor failure is failure of the heating element. Most oxygen sensors have a heating element to rapidly bring the sensor up to the high (400 to 600 degrees Fahrenheit) operating temperature it needs. This heating element is a bit like the element in a hair dryer that glows when it is hot. Over time, the punishment dealt by the exhaust gases to the oxygen sensor will damage the heating element. This condition will set a check engine code that necessitates the replacement of the oxygen sensor.

* There can be oxygen sensor problems that aren’t related to a faulty sensor. If there is an exhaust system leak that allows false, or unaccounted for, outside air to reach the sensor, it will produce false readings that are sent back to the engine computer. This may cause a false compensation to the air/fuel mixture that will produce dirtier vehicle emissions.

* An engine misfire can pulse excessive amounts of oxygen to the oxygen sensor and set an oxygen sensor code when there isn’t a problem with the sensor itself.

Always have a trained emissions diagnostic technician inspect and determine why the oxygen sensor needs attention so that only the proper repair is performed. It is recommended to always use a factory-quality oxygen sensor with the proper connector. The use of a universal oxygen sensor can cause poor emissions system performance. This is due to the fact that since 1990, the operating tolerance allowed by engine computer programming gets more rigorous each model year. Universal oxygen sensors have thus become outmoded because their operating tolerance is too generic.
About this Repair: Oxygen Sensor Replacement - Front
What to watch out for:

* Exhaust leaks can trigger an oxygen sensor trouble code, but the oxygen sensor does not require repair. Repairing the exhaust leak will resolve the problem.

* On vehicles 1996 and newer, using an inexpensive "universal" oxygen sensor will cause problems with the emissions system.

Why this happens:

* A failed oxygen sensor may result in the vehicle failing an emissions test. The failed sensor will result in a trouble code being set and the "Check Engine Light" coming on.

* Oxygen sensors will fail if they are contaminated with oil, coolant, or silicone. They commonly fail after a head gasket has been repaired.

* If fluid contamination has caused an oxygen sensor to fail, the source of the fluid must be diagnosed and resolved, or any new sensor will be immediately ruined.

Price range for Labour of Front Oxygen Sensor Replacement: £0.00 - £0.00



Return to the top of the page
Muffler Replacement

The muffler (exhaust box) is a part of the exhaust system. The muffler reduces the noise created by exhaust gases emitted from the engine.

Exhaust gases are forced out of the engine, routed under the vehicle, and expelled at the rear of the vehicle. Exhaust gas contains a large percentage of water vapour, which over time will rust and degrade the exhaust system.

Holes in the exhaust system may allow exhaust gas to leak into the vehicle. If inhaled, these gases are harmful to its occupants.

The vehicle exhaust system should be inspected periodically for damage that could cause restriction of the exhaust, which may result in a loss of power. The exhaust system should also be periodically inspected for leaks that could become potentially harmful to occupants of the vehicle.

To replace the muffler or other exhaust components, the vehicle is raised to gain access to the underside of the vehicle.

Price range for Labour of Muffler Replacement: £0.00 - £0.00



Return to the top of the page
Oxygen Sensor Replacement

Oxygen sensors are key components in the vehicle's pollution control system. The front oxygen sensor produces a signal that the fuel injection computer uses to determine if the engine requires more or less fuel to optimize fuel consumption. The rear oxygen sensor monitors the efficiency of the catalytic converter.

Over time, oxygen sensors become "lazy," and their output signal deteriorate. An engine that burns oil or has a blown head gasket (which allows antifreeze into the exhaust system) may contribute to the failure of the sensor. Modern sensors have an electrical heating circuit built into them, which is prone to failure over time.

To replace an oxygen sensor, its electrical connection is disconnected, the sensor is removed from the exhaust system, and the new sensor is installed.

Mechanics Corner: More Technical Detail

Oxygen sensors constantly monitor the oxygen content in the exhaust gases and sends this information to the engine management computer 10 or more times per second.

The first oxygen sensors were mounted only in front of the catalytic converter, but as of 1996, an oxygen sensor is mounted before and after each catalytic converter.

* The purpose of the front oxygen sensor, which is mounted before the catalytic converter, is to measure how rich or lean the gases are as the gases exit the combustion chambers. Depending upon whether the exhaust gas is lean (high in oxygen content) or rich (low in oxygen content), the amount of fuel entering the engine is adjusted by the engine management computer to try and maintain an ideal mixture that produces the lowest emissions output from the catalytic converter.

* The purpose of the rear oxygen sensor is to monitor the oxygen content of the exhaust gases leaving the catalytic converter. This gives the emission system a way to monitor the operation and efficiency of the catalytic converters. The rear oxygen sensor checks several things in the post–catalytic converter gases. It measures the amount of oxygen, or peak threshold, in the exhaust gases and follows how fast the amount of oxygen changes. On some vehicles, the rear oxygen sensor is mounted midway in the catalytic converter to measure how efficiently the reduction bed converts NOx by checking the amount of oxygen that is released back into the exhaust flow.

With each new model year, manufacturers are adding more oxygen sensors to better manage engine operation. Some high-performance engines have an oxygen sensor for each cylinder as well as one for the rear of each catalytic converter: for an 8-cylinder engine, that can mean 10 oxygen sensors.

Replacing the front oxygen sensor varies from vehicle to vehicle. Some vehicles have only one front oxygen sensor and are as easy to replace as a single spark plug. Other vehicles have one or more oxygen sensors per bank, or group, of cylinders, and can be very difficult to access. The front oxygen sensor is usually on or near the exhaust manifold but in front of the catalytic converters. Usually, the electrical connector is first disconnected and then the sensor is unscrewed from the exhaust system. These initial steps can be rather tricky because some vehicles have oxygen sensor wiring that enters the passenger compartment, so disconnecting and removing then can take half an hour or more to complete.

The performance of any oxygen sensor deteriorates over time: the amount of the signal change, or bandwidth, as well as the speed, or frequency, of signal change decreases. The engine management computer is constantly monitoring this performance, and when the programmed envelope of acceptable oxygen sensor performance has been breached, the computer will set a fault code and illuminate the check engine light.

* In some cases, the oxygen sensor is contaminated by something in the exhaust gases, such as coolant from a leaking head gasket or oil from a worn engine. Even the wrong type of gasket sealer with silicone can contaminate, or foul, an oxygen sensor. If the sensor has any noticeable colouring from a leaking substance, the source of the substance must be located and repaired or any new oxygen sensor will be ruined in short order.

* Another common reason for oxygen sensor failure is failure of the heating element. Most oxygen sensors have a heating element to rapidly bring the sensor up to the high (400 to 600 degrees Fahrenheit) operating temperature it needs. This heating element is a bit like the element in a hair dryer that glows when it is hot. Over time, the punishment dealt by the exhaust gases to the oxygen sensor will damage the heating element. This condition will set a check engine code that necessitates the replacement of the oxygen sensor.

* There can be oxygen sensor problems that aren’t related to a faulty sensor. If there is an exhaust system leak that allows false, or unaccounted for, outside air to reach the sensor, it will produce false readings that are sent back to the engine computer. This may cause a false compensation to the air/fuel mixture that will produce dirtier vehicle emissions.

* An engine misfire can pulse excessive amounts of oxygen to the oxygen sensor and set an oxygen sensor code when there isn’t a problem with the sensor itself.

Always have a trained emissions diagnostic technician inspect and determine why the oxygen sensor needs attention so that only the proper repair is performed. It is recommended to always use a factory-quality oxygen sensor with the proper connector. The use of a universal oxygen sensor can cause poor emissions system performance. This is due to the fact that since 1990, the operating tolerance allowed by engine computer programming gets more rigorous each model year. Universal oxygen sensors have thus become outmoded because their operating tolerance is too generic.
About this Repair: Oxygen Sensor Replacement
What to watch out for

* On vehicles 1996 and newer, using an inexpensive "universal" oxygen sensor will cause problems with the emissions system.

Why this happens:

* A failed oxygen sensor may result in the vehicle failing an emissions test. The failed sensor will result in a trouble code being set and the "Check Engine Light" being lit.

* Oxygen sensors will fail if they are contaminated with oil, coolant, or silicone. They commonly fail after a head gasket has been repaired.

* Exhaust leaks can trigger an oxygen sensor trouble code, but the oxygen sensor does not require repair. Repairing the exhaust leak will resolve the problem.

* If fluid contamination has caused an oxygen sensor to fail, the source of the fluid must be diagnosed and resolved, or any new sensor will be immediately ruined.

Price range for Labour of Oxygen sensor Replacement: £0.00 - £0.00



Return to the top of the page
Rear Oxygen Sensor Replacement

Rear oxygen sensors are key components of the vehicle's exhaust system and monitor the efficiency of the catalytic converter.

Over time, oxygen sensors become "lazy," and their output signal deteriorate. An engine that burns oil or has a blown head gasket (which allows antifreeze into the exhaust system) may contribute to the failure of the sensor. Modern sensors have an electrical heating circuit built into them, which is prone to failure over time.

To replace an oxygen sensor, its electrical connection is disconnected, the sensor is removed from the exhaust system, and the new sensor is installed

Mechanics Corner: More Technical Detail

Oxygen sensors constantly monitor the oxygen content in the exhaust gases and sends this information to the engine management computer 10 or more times per second.

The first oxygen sensors were mounted only in front of the catalytic converter, but as of 1996, an oxygen sensor is mounted before and after each catalytic converter.

* The purpose of the front oxygen sensor, which is mounted before the catalytic converter, is to measure how rich or lean the gases are as the gases exit the combustion chambers. Depending upon whether the exhaust gas is lean (high in oxygen content) or rich (low in oxygen content), the amount of fuel entering the engine is adjusted by the engine management computer to try and maintain an ideal mixture that produces the lowest emissions output from the catalytic converter.

* The purpose of the rear oxygen sensor is to monitor the oxygen content of the exhaust gases leaving the catalytic converter. This gives the emission system a way to monitor the operation and efficiency of the catalytic converters. The rear oxygen sensor checks several things in the post–catalytic converter gases. It measures the amount of oxygen, or peak threshold, in the exhaust gases and follows how fast the amount of oxygen changes. On some vehicles, the rear oxygen sensor is mounted midway in the catalytic converter to measure how efficiently the reduction bed converts NOx by checking the amount of oxygen that is released back into the exhaust flow.

With each new model year, manufacturers are adding more oxygen sensors to better manage engine operation. Some high-performance engines have an oxygen sensor for each cylinder as well as one for the rear of each catalytic converter: for an 8-cylinder engine, that can mean 10 oxygen sensors.

Replacing the front oxygen sensor varies from vehicle to vehicle. Some vehicles have only one front oxygen sensor and are as easy to replace as a single spark plug. Other vehicles have one or more oxygen sensors per bank, or group, of cylinders, and can be very difficult to access. The front oxygen sensor is usually on or near the exhaust manifold but in front of the catalytic converters. Usually, the electrical connector is first disconnected and then the sensor is unscrewed from the exhaust system. These initial steps can be rather tricky because some vehicles have oxygen sensor wiring that enters the passenger compartment, so disconnecting and removing then can take half an hour or more to complete.

The performance of any oxygen sensor deteriorates over time: the amount of the signal change, or bandwidth, as well as the speed, or frequency, of signal change decreases. The engine management computer is constantly monitoring this performance, and when the programmed envelope of acceptable oxygen sensor performance has been breached, the computer will set a fault code and illuminate the check engine light.

* In some cases, the oxygen sensor is contaminated by something in the exhaust gases, such as coolant from a leaking head gasket or oil from a worn engine. Even the wrong type of gasket sealer with silicone can contaminate, or foul, an oxygen sensor. If the sensor has any noticeable colouring from a leaking substance, the source of the substance must be located and repaired or any new oxygen sensor will be ruined in short order.

* Another common reason for oxygen sensor failure is failure of the heating element. Most oxygen sensors have a heating element to rapidly bring the sensor up to the high (400 to 600 degrees Fahrenheit) operating temperature it needs. This heating element is a bit like the element in a hair dryer that glows when it is hot. Over time, the punishment dealt by the exhaust gases to the oxygen sensor will damage the heating element. This condition will set a check engine code that necessitates the replacement of the oxygen sensor.

* There can be oxygen sensor problems that aren’t related to a faulty sensor. If there is an exhaust system leak that allows false, or unaccounted for, outside air to reach the sensor, it will produce false readings that are sent back to the engine computer. This may cause a false compensation to the air/fuel mixture that will produce dirtier vehicle emissions.

* An engine misfire can pulse excessive amounts of oxygen to the oxygen sensor and set an oxygen sensor code when there isn’t a problem with the sensor itself.

Always have a trained emissions diagnostic technician inspect and determine why the oxygen sensor needs attention so that only the proper repair is performed. It is recommended to always use a factory-quality oxygen sensor with the proper connector. The use of a universal oxygen sensor can cause poor emissions system performance. This is due to the fact that since 1990, the operating tolerance allowed by engine computer programming gets more rigorous each model year. Universal oxygen sensors have thus become outmoded because their operating tolerance is too generic.
About this Repair: Oxygen Sensor Replacement - Rear
What to watch out for

* Exhaust leaks can trigger an oxygen sensor trouble code, but the oxygen sensor does not require repair. Repairing the exhaust leak will resolve the problem.

* It is common for rear oxygen sensors to be incorrectly replaced when addressing a problem with the catalytic converter.

* On vehicles 1996 and newer, using an inexpensive "universal" oxygen sensor will cause problems with the emissions system.

Why this happens:

* A failed oxygen sensor may result in the vehicle failing an emissions test. The failed sensor will result in a trouble code being triggered, which in turns on the "Check Engine Light."

* If fluid contamination has caused an oxygen sensor to fail, the source of the fluid must be diagnosed and resolved, or any new sensor will be immediately ruined.

Price range for Labour of Rear Oxygen Sensor Replacement: £0.00 - £0.00



Return to the top of the page
Air Pump

The air pump helps reduce exhaust emissions from the engine while it's warming up.

After unburned fuel (hydrocarbons, HC) and partially burned fuel (carbon monoxide, CO) leave the engine's combustion chamber, they enter the exhaust system. The air pump pumps oxygen into the exhaust system, where it mixes with the HC and CO. As the oxygen mixes with these gases, the burning process continues, and the emissions from the engine are reduced.



Return to the top of the page
Air Pump Check Valve

The air pump check valve is part of the secondary air injection system. It allows air to be introduced into the exhaust system but prevents the exhaust from entering the air pump system.

After unburned fuel (hydrocarbons, HC) and partially burned fuel (carbon monoxide, CO) leave the engine's combustion chamber, they enter the exhaust system. The air pump pumps oxygen into the exhaust system, where it mixes with the HC and CO. As the oxygen mixes with these gases, the burning process continues, and the emissions from the engine are reduced.



Return to the top of the page
Catalytic Converter

The catalytic converter is a sophisticated 'after burning' device that is designed to complete the combustion of the exhaust gases that pass through it and is a key component in the vehicle's pollution control system. It is a stainless steel container with an inlet and outlet pipe that looks similar to a muffler and is located in the vehicle's undercarriage.

Inside the catalytic converter is a ceramic monolithic structure that has honeycomb like passages running through it. This structure has several sections called 'beds' that are thinly coated with special rare metals that react with the compounds in the exhaust gases to complete the combustion process thereby cleaning or ‘scrubbing’ the exhaust of the harmful emissions.

The first section of the converter is called the reduction bed and is coated with Rhodium. It is called the reduction bed because its purpose is to reduce the Nitrogen Oxide (NOx) gases back in to harmless nitrogen and oxygen.

The next section of the converter is the oxygen storage bed that is coated with Cerium. Its purpose is to maintain an ideal level of oxygen for use by the rear of the converter. It does this by storing and releasing the oxygen that gets released from the reduction of nitrogen oxide (NOx) in the previous reduction bed. The oxygen is then available to be used in the final oxidizing bed which is coated with Platinum and Palladium. The purpose of the oxidizing bed is to complete the combustion of Carbon Monoxide (CO) by adding oxygen. The oxidizing bed also utilizes oxygen to burn any of the raw Hydrocarbons (HC’s) that still remain in the exhaust gases.

The inside of the catalytic converter operates at very high temperatures. It will not even begin to 'light off' until it reaches 400-600 degrees Fahrenheit and typically runs from 1200-1600 degrees depending upon how hard it is being worked. A rich or 'dirty' running engine can make the converter work so hard that it will actually glow red. This is why there are catalytic converter damaging misfire codes that will illuminate the check engine light and even make it steadily flash under severe misfire conditions.



Return to the top of the page
Exhaust Clamps

Exhaust clamps provide a tight connection between pipe sections and other exhaust components.



Return to the top of the page
Exhaust Gas Recirculation Valve

The exhaust gas recirculation valve (EGR valve) recirculates combustion gases—including unburned hydrocarbons—back into the engine intake. This has the desirable effect of lowering the peak flame temperature in the combustion process, thus reducing the production of oxides of nitrogen, a major pollutant.



Return to the top of the page
Exhaust Gas Recirculation Valve Gasket

The exhaust gas recirculation valve gasket (EGR gasket) is a heat-resistant sealing device that prevents gases from leaking between the intake manifold and the exhaust manifold.



Return to the top of the page
Exhaust Gasket Kit

A gasket is a mechanical seal that fills the space between two objects. Gaskets generally prevent leakage of material between the objects when the material inside the objects is compressed.



Return to the top of the page
Exhaust Gaskets

A gasket is a mechanical seal that fills the space between two objects. Gaskets generally prevent leakage of material between the objects when the material inside the objects is compressed.



Return to the top of the page
Exhaust Manifold

The exhaust manifold is the first downstream emission control device. The purpose of the exhaust manifold is to gather the extremely hot exhaust gases from the individual cylinders and channel them into a single header pipe while keeping these gases as hot as possible. Some exhaust manifolds are heavy cast iron devices that are designed to store the extreme heat caused by the still burning exhaust gases leaving the individual cylinders. This helps sustain the burning process of combustion into the next downstream emission device, the catalytic converter.



Return to the top of the page
Exhaust Manifold Gasket

The exhaust manifold gasket is a heat-resistant mechanical seal that prevents exhaust gas leakage between the cylinder head and the exhaust manifold.



Return to the top of the page
Exhaust Manifold to Down Pipe Gasket

This gasket is a heat-resistant mechanical seal that prevents leakage of exhaust gas between the exhaust manifold and the exhaust down pipe.



Return to the top of the page
Exhaust Pipe

The exhaust pipe routes harmful exhaust gas away from the engine, through the catalytic converter and muffler, and out the tail pipe.



Return to the top of the page
Exhaust Tail Pipe

The tail pipe is a metal tube attached to the exhaust pipe. It discharges exhaust gases into the air outside of the car. The tail pipe is the only visible part of the exhaust system.



Return to the top of the page
Front Oxygen Sensor

The front oxygen sensor is mounted in the exhaust stream behind (but close to) the engine and ahead of the catalytic converter. The sensor generates an electrical signal, which is monitored by the engine electronic control unit primarily to maintain the air/fuel ratio.

The oxygen sensor is a device that constantly monitors the oxygen content in the exhaust gases and sends this information back to the engine management computer ten or more times per second.

Originally, oxygen sensors were only mounted before the catalytic converter, but since 1996, there are oxygen sensors before and after each catalytic converter. The purpose of the front oxygen sensor (the one before the catalytic converter) is to measure the exhaust gases exiting the combustion chambers to determine how rich (high oxygen content) or lean (low oxygen content) they are. Depending upon whether the exhaust gas is lean or rich, the engine management computer adjusts the amount of fuel going into the engine to try to maintain an ideal mixture that produces the lowest emissions output from the catalytic converter.

The purpose of the rear oxygen sensor is to monitor the oxygen content of the exhaust gases leaving the catalytic converter. This provides the emissions system with a way to monitor the operation and efficiency of the catalytic converter. The rear oxygen sensor measures the amount of oxygen or "peak threshold" in the exhaust gases and it follows how fast the amount of this gas (oxygen) changes.

On some vehicles, the rear oxygen sensor is mounted midway in the catalytic converter. By checking the amount of oxygen that is released back into the exhaust flow, the rear oxygen sensor measures how efficient the reduction bed is converting nitrogen oxide (NOx).

To better manage the operation of the engine, manufacturers are adding more oxygen sensors with each new model year. Some high-performance engines have an oxygen sensor for each cylinder (as well as one for the rear of each catalytic converter), so an 8-cylinder engine can have as many as ten oxygen sensors.



Return to the top of the page
Gaskets

A gasket is a mechanical seal that fills the space between two objects. Gaskets generally prevent leakage of material between the objects when the material inside the objects is compressed.



Return to the top of the page
Intake Manifold

An intake manifold is an air channelling and holding device whose purpose is to receive fresh air from the throttle body and then hold and distribute it to the individual cylinders through their intake ports in the cylinder head(s).



Return to the top of the page
Intake Manifold Gasket

The intake manifold gasket is a mechanical seal that prevents air leaks and seals coolant passages between the intake manifold and cylinder head.



Return to the top of the page
Muffler

The muffler, or exhaust box, is located on the vehicle's underside. It reduces the noise caused by emitting exhaust.



Return to the top of the page
Oxygen Sensor

To operate efficiently, the engine requires a specific ratio of air to fuel, approximately 14 to 1. The oxygen sensor—placed in the exhaust stream but close to the engine— generates an electrical signal that is proportionate to the amount of oxygen remaining in the exhaust. The engine electronic control module utilizes this information to maintain that ratio by continuously adjusting the amount of fuel introduced into the engine.

The oxygen sensor is a device that constantly monitors the oxygen content in the exhaust gases and sends this information back to the engine management computer ten or more times per second.

Originally, oxygen sensors were only mounted before the catalytic converter, but since 1996, there are oxygen sensors before and after each catalytic converter. The purpose of the front oxygen sensor (the one before the catalytic converter) is to measure the exhaust gases exiting the combustion chambers to determine how rich (high oxygen content) or lean (low oxygen content) they are. Depending upon whether the exhaust gas is lean or rich, the engine management computer adjusts the amount of fuel going into the engine to try to maintain an ideal mixture that produces the lowest emissions output from the catalytic converter.

The purpose of the rear oxygen sensor is to monitor the oxygen content of the exhaust gases leaving the catalytic converter. This provides the emissions system with a way to monitor the operation and efficiency of the catalytic converter. The rear oxygen sensor measures the amount of oxygen or "peak threshold" in the exhaust gases and it follows how fast the amount of this gas (oxygen) changes.

On some vehicles, the rear oxygen sensor is mounted midway in the catalytic converter. By checking the amount of oxygen that is released back into the exhaust flow, the rear oxygen sensor measures how efficient the reduction bed is converting nitrogen oxide (NOx).

To better manage the operation of the engine, manufacturers are adding more oxygen sensors with each new model year. Some high-performance engines have an oxygen sensor for each cylinder (as well as one for the rear of each catalytic converter), so an 8-cylinder engine can have as many as ten oxygen sensors.



Return to the top of the page
Rear Oxygen Sensor

Mounted in the exhaust stream behind the catalytic converter, the rear oxygen sensor produces an electrical signal proportional to the exhaust gas composition. To monitor catalytic converter efficiency, the engine electronic control unit compares this signal to the one from the front oxygen sensor.

The oxygen sensor is a device that constantly monitors the oxygen content in the exhaust gases and sends this information back to the engine management computer ten or more times per second.

Originally, oxygen sensors were only mounted before the catalytic converter, but since 1996, there are oxygen sensors before and after each catalytic converter. The purpose of the front oxygen sensor (the one before the catalytic converter) is to measure the exhaust gases exiting the combustion chambers to determine how rich (high oxygen content) or lean (low oxygen content) they are. Depending upon whether the exhaust gas is lean or rich, the engine management computer adjusts the amount of fuel going into the engine to try to maintain an ideal mixture that produces the lowest emissions output from the catalytic converter.

The purpose of the rear oxygen sensor is to monitor the oxygen content of the exhaust gases leaving the catalytic converter. This provides the emissions system with a way to monitor the operation and efficiency of the catalytic converter. The rear oxygen sensor measures the amount of oxygen or "peak threshold" in the exhaust gases and it follows how fast the amount of this gas (oxygen) changes.

On some vehicles, the rear oxygen sensor is mounted midway in the catalytic converter. By checking the amount of oxygen that is released back into the exhaust flow, the rear oxygen sensor measures how efficient the reduction bed is converting nitrogen oxide (NOx).

To better manage the operation of the engine, manufacturers are adding more oxygen sensors with each new model year. Some high-performance engines have an oxygen sensor for each cylinder (as well as one for the rear of each catalytic converter), so an 8-cylinder engine can have as many as ten oxygen sensors.


HEATING AND AIRCONDITIONING



Return to the top of the page
Heating and Air Conditioning

Your car's heating and air conditioning systems control the temperature of the vehicle's cabin. So whether it’s Fourth of July in Death Valley or Christmas in Green Bay, at least you’ll be comfortable in your car—provided these systems are working properly.

Related Services & Repairs
Return to the top of the page
* AC Compressor AC Condenser
Return to the top of the page
* AC Evaporator Heater Blower Motor Heater Control Valve Heater Core Refrigerant Recharge Thermostat

The AC system operates by compressing and expanding refrigerant to transition it between liquid and gaseous forms. Liquid absorbs heat when it becomes a gas; gas gives off heat when it becomes a liquid. Using these thermodynamic properties, heat is removed from the passenger compartment and released to the outside air while cool air enters the passenger compartment.

Cars use two different types of refrigerant.

* R12 (Freon) was invented in 1928 and discontinued in the early 1990s after being found to have significant ozone layer–depletion properties.

* R134a is a more environmentally friendly option to R12 used in modern cars and to recharge AC systems in older cars.

The AC system consists of 5 components.

* The compressor is the heart of the system. The compressor is a belt-driven pump fastened to the engine. Refrigerant is compressed and then turned into a hot gas before travelling to the condenser.

* The condenser is where heat dissipation occurs. It uses the air passing through to absorb heat, so the refrigerant can cool and become a liquid.

* The dryer functions as a refrigerant filter, removing moisture and contaminants.

* The orifice tube/expansion valve is a filter that regulates how much refrigerant is released into the evaporator. In older cars, the refrigerant flow is measured and regulated by an expansion valve. As the refrigerant passes through either device, it expands and becomes partly vaporized, rapidly cooling it off.

* The evaporator removes heat from the inside the car. Refrigerant enters the bottom of the evaporator as a liquid. The warm air passing through the evaporator fins causes the refrigerant to boil. As it boils, it absorbs large amounts of heat. This heat is carried off with the refrigerant to the outside of the vehicle, leaving cooled air. Fans blow the cooled air into the passenger compartment.

If your car is overheating, turn off the AC, open all the windows, and blast the heater. This is because your car's heating system is a smaller version of the engine’s cooling system. Hot engine coolant circulates through the heater core, which is basically a mini radiator. A fan (blower motor) that sits in front of the heater core moves the air past it. As this air passes over the core, it heats up and passes through the heater vents into the passenger compartment. Although dissipating this hot air might not keep you cool and comfortable on a hot day, it will help prevent your car from overheating, so you can visit your mechanic before serious engine damage occurs.



Return to the top of the page
Air Conditioning Compressor Replacement

Sometimes referred to as AC Compressor, Air Conditioning Compressor, AC Compressor Replacement

An engine-driven fan belt powers the air conditioning compressor, which is mounted on the engine.

To replace the air conditioning compressor, the air conditioning system refrigerant is flushed and the high pressure lines to the compressor are removed. The compressor is detached from the engine and replaced with the new compressor. Compressor lubricant and the refrigerant are replaced.

The AC system should be operated at least once a month to circulate the refrigerant—even during the winter. The AC system operates at very high pressures. Special tools and knowledge are needed to work on it; this work must be carried out by competent, trained technicians.
About this Repair: AC Compressor Replacement
What to watch out for

* "Stop leak" compounds are not recommended, as they are temporary solutions and can damage AC components, resulting in an expensive repair.

Recommendations:

* We recommend replacing the AC Drier when the AC Compressor is replaced. The AC Drier acts as a filter for the AC system, and a new part will keep the repaired system clean.

* We recommend flushing the AC system when replacing an AC Compressor to remove any debris caused by the failed component.

Why this happens:

* AC Compressors require replacement if they are found to be leaking oil. They also may fail a dye and leak check.

* Failing AC Compressors can make unusually loud noises while operating.

* Any restrictions in the AC system need to be identified and repaired, or a recurring problem with the AC Compressor is likely.

Price range for Labour of Air Conditioning Compressor Replacement: £0.00 - £0.00



Return to the top of the page
Air Conditioning Condenser Replacement

The air conditioning condenser is located in the engine compartment in front of the vehicle's radiator.

To replace the air conditioning condenser, the AC system refrigerant is flushed, the metal lines to the condenser are removed, and the condenser is detached from the radiator. The new condenser is installed, and the refrigerant replaced.

The location of the AC condenser makes it prone to damage if the vehicle is involved in a front-end collision. If such a collision occurs, the AC system should be closely inspected to ensure that it is operating correctly and not in danger of failing at a later date.

The AC system should be operated at least once a month to circulate the refrigerant—even during the winter. The AC system operates at very high pressures. Special tools and knowledge are needed to work on it; this work must be carried out by competent, trained technicians.
About this Repair: AC Condenser Replacement
What to watch out for

* "Stop leak" compounds are not recommended, as they are temporary solutions and can damage AC components, resulting in an expensive repair.

Recommendations:

* We recommend replacing the AC Drier when the AC Condenser is replaced. The AC Drier acts as a filter for the AC system, and a new part will keep the repaired system clean.

Why this happens:

* Failing AC Condensers can be the cause for the AC to make unusually loud noises while operating.

* AC Condensers require replacement if they fail a dye and leak check.

* Any restrictions in the AC system need to be identified and repaired, or a recurring problem with the AC Condenser is likely.

Price range for Labour of Air Conditioning Condenser Replacement: £0.00 - £0.00



Return to the top of the page
Air Conditioning Evaporator Replacement

The air conditioning evaporator cools and dehumidifies air in the passenger compartment of the vehicle. It is located behind the dashboard.

It is difficult to detect leaks in the AC evaporator because it's located behind the vehicle’s dashboard.

To replace the evaporator, refrigerant must be flushed from the system. Replacement of the evaporator usually involves major disassembly of the vehicle’s dashboard, centre console, and much of the interior in order to gain access to the evaporator.

The AC system should be operated at least once a month to circulate the refrigerant—even during the winter. The AC system operates at very high pressures. Special tools and knowledge are needed to work on it; this work must be carried out by competent, trained technicians.
About this Repair: AC Evaporator Replacement
Why this happens

* Failing AC Evaporators can be the cause for the AC to make unusually loud noises while operating.

* AC Evaporators require replacement if they fail a dye and leak check.

* Any restrictions in the AC system need to be identified and repaired, or a recurring problem with the AC Evaporator is likely.

Price range for Labour of Air Conditioning Evaporator Replacement: £0.00 - £0.00



Return to the top of the page
Air Conditioning Recharge / Re-gas

It may be necessary to recharge the air conditioning system refrigerant if the system has lost its cooling efficiency. Before any AC system repairs are performed, the system must be free of moisture and contaminates and leaks should already be repaired.

To recharge the AC system, gauges are attached to the AC system to measure pressures in the system, and refrigerant is added as needed.

AC systems should be worked on only by competent, trained personnel.
About this Repair: AC Recharge

Recommendations:

* We recommend using leak detection dye when recharging the AC to detect any problems with the AC systems.

Why this happens:

* AC systems require recharging when they become weak and do not perform well, or start to make unusual noise.

* AC systems should not require recharging more than every 3 years, and do not require recharging if they are functioning properly.

* "Stop leak" compounds are not recommended, as they are temporary solutions and can damage AC components, resulting in an expensive repair.

Price range for Labour of Air Conditioning Recharge Replacement: £0.00 - £0.00



Return to the top of the page
Heater Blower Motor Replacement

The heater blower motor is located behind the dashboard. The driver can control the speed at which the blower motor operates via buttons, slides, or dials on the dashboard. The blower motor forces air through a heater radiator behind the dashboard to provide heat for the passenger compartment. Alternatively, the motor blows air through the air conditioning evaporator to provide cold air to the passenger compartment.

Heater motors on many vehicles may operate only at high speeds if the heater control resistor unit fails. Mice may also build nests in the heater blower fan, filling it with nesting material that can cause the fan to jam or malfunction.

To access and replace the blower motor, some disassembly of the dashboard and interior trim is necessary.
About this Repair: Heater Blower Motor Replacement
Why this happens

* Any fluid leaks near the heater blower need to be resolved or the new heater blower will be ruined.

* Heater blowers can be damaged by fluid leaking from a heater core or evaporator.

* After the repair, the heater should run normally in all modes, such as defrost, heat, etc., and the motor should be quiet and not vibrate.

Price range for Labour of Heater Blower Motor Replacement: £0.00 - £0.00



Return to the top of the page
Heater Control Valve Replacement

To control the temperature in the passenger compartment, the driver operates a lever, slide, or dial on the dashboard that is attached to a heater valve. This valve, usually located at the rear of the engine compartment, controls how much hot coolant passes through the heater core (located behind the dashboard).

If it is no longer possible to turn the vehicle's heat on or off, or if the valve leaks coolant, replacement of the heater valve may be necessary.

To replace the heater valve, the cooling system is drained, coolant hoses and the control cable are removed from the heater valve, and the valve is replaced. The components are then reassembled, and the cooling system is filled with coolant. In some vehicles, the heater control valve may be located behind the dashboard, which adds complexity to this repair.
About this Repair: Heater Control Valve Replacement

Recommendations:

* The shop should inspect all of the heater hoses when replacing the heater control valve.

* If the heater control valve is being replaced because it is corroded, we recommended flushing the coolant to prevent additional problems.

Why this happens:

* Heater control valves are often replaced because they leak or because the heater hoses are being replaced and it's economical to replace the valve as well.

Price range for Labour of Heater Control Valve Replacement: £0.00 - £0.00



Return to the top of the page
Heater Core Replacement

Hot coolant from the engine is circulated through the heater core to provide heat in the passenger compartment of a vehicle. The heater core is located behind the dashboard. The driver operates a lever that controls how much hot coolant passes through the heater core.

To replace the heater core, the cooling system is drained and major disassembly of the dashboard and interior of the vehicle is necessary. If the vehicle has air conditioning, it is likely that the AC system will have to be evacuated and recharged during this repair.
About this Repair: Heater Core Replacement

Recommendations:

* We recommend using a high-quality replacement heater core. Cheap heater cores tend to leak and not last very long.

* The heater hoses should be inspected when replacing a heater core. Problems with the heater hoses can cause similar problems to a failing heater core and are much cheaper to correct.

Why this happens:

* A failed heater core can result in the car windows fogging up, a coolant leak under the vehicle but well behind the engine, leaks into the vehicle interior, or engine overheating.

* Worn engine mounts allow the engine to move more than normal, which can damage heater core connections. Worn mounts should be replaced to avoid damage.

Price range for Labour of Heater Core Replacement: £0.00 - £0.00



Return to the top of the page
Air Conditioning Compressor

The air conditioning compressor is used to compress refrigerant gas, and then delivers it to the condenser. It is driven by the AC drive belt.



Return to the top of the page
Air Conditioning Condenser

The air conditioning condenser acts as a heat exchanger, cooling the compressed air conditioning refrigerant and turning it from a vapour into a liquid.



Return to the top of the page
Air Conditioning Drive Belt


The air conditioning drive belt is a flexible belt made of rubber (and reinforced with cord) that is powered by the engine to rotate the air conditioning compressor.



Return to the top of the page
Air Conditioning Dryer

The AC dryer removes moisture from the refrigerant in the air conditioning system.



Return to the top of the page
Air Conditioning Evaporator

The evaporator serves as the heat absorption component of the air conditioning system. Warm air is drawn through the evaporator and cooled, then directed to the interior of the vehicle. It has a secondary benefit of dehumidification.



Return to the top of the page
Air Conditioning Service Kit R12

Older vehicles used the refrigerant R12, which has become prohibitively expensive. It may be more cost effective to convert the system to the refrigerant R134a, which is much less expensive.

The air conditioning system must be thoroughly flushed, and some air conditioning system components replaced, in order to successfully convert from one refrigerant to another.



Return to the top of the page
Air Conditioning System Flush

An air conditioning system flush kit removes contaminants, moisture, and acid from R12, R134a, and R22 AC systems.



Return to the top of the page
Expansion Valve

The expansion valve lowers the pressure of the refrigerant and determines the correct amount of refrigerant going into the air conditioning evaporator.



Return to the top of the page
Heater Blower Motor

The Heater Blower Motor is a fan that blows air into the passenger compartment.



Return to the top of the page
Heater Control Valve

The heater control valve controls the amount of hot engine coolant flowing through the heater core, thus affecting the heater temperature.



Return to the top of the page
Heater Core

The heater core is a small radiator located behind the dashboard. When the heating controls are operated, hot coolant from the engine is diverted through the heater core, allowing heated air into the passenger compartment.



Return to the top of the page
Heater Hose

Heater hoses provide a flexible connection for coolant flow between the engine and the heater core.



Return to the top of the page
Hose Clamps

A hose clamp attaches and seals a hose to a fitting.

Various strategies to mechanically join or clamp the hose are employed to ensure an adequate seal. A time-honoured design uses a worm gear to draw the strap portion of the clamp around the hose. The hose is tightened with a screwdriver. The drawback to this design is that the hose can be over tightened during installation or become overly tight as the hose and its fitting expand with temperature increase.

An alternative and prevalent design—the circular spring or "Corbin" clamp—utilizes a special plier-like installation tool to fit over the hose. Because of its "spring" construction, the correct clamping force is built into the self-applying clamp. By design, the clamp cannot be over or under tightened and will expand and contract along with the hose.



Return to the top of the page
Refrigerant (R12/R134a)

A specially formulated "high-temperature" refrigerant that exchanges heat in the AC system.



Return to the top of the page
Refrigerant Lubricant (R12/R134a)

AC systems mix oil with the refrigerant to lubricate various parts, such as the compressor.


SCHEDULED MAINTENANCE



Return to the top of the page
Scheduled Maintenance

Scheduled Maintenance, or preventative maintenance, is the regular schedule of services that vehicles manufacturers prescribe to keep a car running well and safely. Maintenance schedules vary by vehicle, driving style, and driving conditions.
Are You a “Normal” or “Severe” Driver?

When it comes to maintenance advice, consumers are confronted with numerous recommendations and opinions. When the owner’s manual recommends one type of service, a quick lube franchise recommends a second, and the dealership advises a third, it’s no wonder consumers are afraid they’ll be ripped off by paying for service they don’t really need. Sometimes it’s impossible to know who’s telling the truth and who isn’t.

The truth is in the owner’s manual. Manufacturers define maintenance schedules for your car, not dealerships—and certainly not quick lube franchises. Most manufacturers divide maintenance schedules into “normal” and “severe” driving conditions.

You might think the conditions you put your car under aren’t considered severe, but if you frequently do any of the following, then your car maintenance should indeed follow the “severe" driving conditions schedule:

* Take short trips of less than 10 miles.
* Drive in heavy traffic with many stops and starts.
* Drive at high rates of speed.
* Tow heavy loads or drive off-road.
* Drive in dusty conditions.
* Drive in extremely cold or extremely hot climates.

Surprised? Many consumers are.

If the above conditions are severe, then what’s normal?

* Trips of 10 miles or more.
* Sustained speeds of 50 to 75 miles an hour.
* Driving in low-traffic situations with few stops and starts.
* Ambient temperatures above freezing and below 95 degrees Fahrenheit.

Determine what your expectations and priorities are to make the most informed decisions about your car’s maintenance schedule. A mother of small children may make decisions based on safety. A person commuting to work may be concerned about fuel economy. A student might make maintenance decisions based on cash flow—or lack thereof. Each of us has different priorities and circumstances.

As sensible car owners, we all must assume responsibility for doing the basics. Periodically checking tire pressure, engine oil, and coolant levels can dramatically increase the life of your car and potentially save you thousands of pounds in repairs down the road. And not only does a well-maintained car last longer and save money in the long run, but it’s also much safer for both you and your passengers.



Return to the top of the page
Air Filter Replacement

The air filter prevents dirt and debris from entering the engine, which could otherwise cause premature engine wear.

The air filter should be inspected, cleaned, and/or replaced every 12,000 miles.

To replace the engine's air filter, it is removed from the air filter housing, the housing is cleaned, and the new air filter is installed.
About this Repair: Air Filter Replacement

Recommendations:

* We recommend considering replacing the air filter every year or every 12,000 to 15,000 miles.

Why this happens:

* If oil has contaminated the air filter, it should be replaced. Oil leaking onto the air filter may indicate a problem with the PCV system.

* Air filters need to be replaced frequently in vehicles driven in dusty and sandy areas.

Price range for Labour of Air Filter Replacement: £0.00 - £0.00



Return to the top of the page
Automatic Transmission Fluid Change

Automatic transmission fluid lubricates and removes heat from internal components in the transmission.

Transmission fluid should be changed every 30,000 miles or more frequently if the vehicle is used for towing or carrying heavy loads. Transmission fluid should be reddish in colour. If it is brown or smells burnt, it needs to be replaced.

When replacing the transmission fluid, first the mechanic drives the vehicle to get the fluid warm and then removes the drain plug at the bottom of the transmission, allowing the fluid to drain.

The transmission is then filled with fresh fluid, and the engine is started. With the engine running and the transmission in "Park," the mechanic checks the level of the transmission fluid on the dipstick. Then the vehicle is driven once more, and the fluid level rechecked; if needed, more fluid is added.

Using the wrong automatic transmission fluid may invalidate the manufacturer's warranty and affect the shift characteristics of the transmission. Consult the owner’s manual for information on the kind of fluid to use.

Many automatic transmissions have a filter that can be replaced when changing the transmission fluid. Changing this filter may allow a closer examination of the fluid for debris, which may be a sign that the transmission is about to fail.
About this Repair: Automatic Transmission Fluid Change

Recommendations:

* We recommend that you consider changing the transmission fluid every 30,000 miles.

Why this happens:

* After the fluid change, shifting while driving and while shifting into and out of park should be smooth.

Price range for Labour of Automatic Transmission Fluid Change: £0.00 - £0.00



Return to the top of the page
Cabin Air Filter Replacement

Located either behind the dashboard or in the engine compartment, the cabin air filter prevents dirt, pollen, and other debris from entering the passenger compartment through the climate control system. Because the filter reduces dust and particles in the cabin, it also increases the reliability of various electronic components (e.g. relays, switches, and sensors).

Manufacturers generally recommend inspection or replacement of the cabin air filter every 15,000 to 30,000 miles.

If the cabin air filter is located behind the dashboard, it may be necessary to remove the glove box or trim panels beneath the dashboard to gain access to the filter. If the filter is located in the engine compartment, replacement is usually quick and straightforward.
About this Repair: Cabin Air Filter Replacement
Why this happens

* The Cabin Air Filter prevents pollen and dirt from entering the passenger compartment and generally does not require replacement as frequently as an engine air filter.

Price range for Labour of Cabin Air Filter Replacement: £0.00 - £0.00



Return to the top of the page
Cooling System Coolant Change

The cooling system uses coolant (a mixture of antifreeze and water) to remove heat produced by the engine. The cooling system needs to be flushed to remove debris that could lower its efficiency.

The engine’s cooling system should be flushed every second year or every 30,000 miles to prevent the radiator from getting clogged with debris. Manufacturers may specify particular types of coolant to be used in their engines; consult your owner’s manual for more information on the correct coolant to use.

To flush the system, drain plugs in the radiator and engine block are removed to allow coolant to exit. After the engine and radiator are drained, the plugs are reinstalled, fresh coolant is put into the radiator and coolant expansion tank, and air is removed from the cooling system.

Once the cooling system is full, the engine is started and run until it reaches normal operating temperature. Then the cooling system is allowed to cool down. Finally, the cooling system fluid level is checked and, if necessary, more fluid is added.
About this Repair: Coolant Replacement/Flush

Recommendations:

* We recommend having the coolant flushed every 30,000 miles.

* Vehicles with more than 90,000 miles may benefit from a thermostat replacement when the cooling system is flushed.

* The shop should inspect the entire cooling system.

Why this happens:

* Dirty coolant may trigger trouble codes, and cause dashboard warning lights to illuminate.

* Dirty or smelly coolant indicates that a system flush may be needed.

Price range for Labour of Cooling System Coolant Flush & Change: £0.00 - £0.00



Return to the top of the page
Manual Transmission Fluid Replacement

Manual transmission fluid lubricates and removes heat from internal components in the manual transmission (also called a gearbox).

A manual transmission, also known as a stick shifter gearbox, should have the fluid replaced every 30,000 miles to ensure proper lubrication of the gears and bearings within the gearbox.

To replace the manual transmission fluid, the mechanic drives the vehicle to get the fluid warm. Then, s/he removes the drain plug at the bottom of the transmission to allow the fluid to drain. The plug is then reinserted, and the transmission is filled with fresh fluid.

Manual transmissions generally use gear oil, but may use common engine oil; check the owner’s manual for the recommended lubricant.
About this Repair: Manual Transmission Fluid Change

Recommendations

* We recommend changing manual transmission fluid every 30,000 miles.

* Dirty or metallic transmission fluid indicates that the system would benefit from a fluid change and flush.

* High-quality synthetic transmission fluid will help extend the life of transmission components.

Why this happens:

* Noise from the transmission most often will not be resolved by a fluid change. Noise from or incorrect operation of the transmission is normally a sign of a deeper mechanical problem.

* We advise changing the transmission fluid when any significant repair work is being performed on the transmission.

Price range for Labour of Manual Transmission Fluid Change: £0.00 - £0.00



Return to the top of the page
Oil Life Monitor Systems

From the 1970s until the mid 1990s, the standard oil change interval was “change your oil every 3000 miles or every 3 months, whichever comes first”. This included all makes and models of cars and light trucks.

Then, in the mid 1990s, vehicles started to incorporate automatic ‘oil change is due’ reminder systems that were based on several computer generated criteria.

* Vehicle systems tracked the number of gallons of fuel consumed and when that total reached a specified threshold an “oil change is due’ message was displayed in the instrument cluster on vehicle start up.

* Vehicle systems deploy a sophisticated oil viscosity measuring device installed inside the engine oil pan that follows the rise and fall of a flotation device that changes its height as the oil heats up and expands and then as the oil cools down and contracts. When this rate of viscosity change reaches specified criteria, the driver is alerted that an oil change is due.

* Other systems track the amount of miles driven at city speeds versus the amount of miles driven at highway speeds.

And many of the most sophisticated systems use all of these tracking criteria simultaneously to calculate the time and or mileage when an ‘oil change’ is due. There was one result that all of these systems created. They all extended the time and mileage between oil changes. Some extended the interval from 3000 miles to 10,000 miles or more, while some of the most modern vehicle systems are designed to only require a single oil change per year.

* The quality of engine design and manufacturing has improved dramatically over the last 30 years. New breakthroughs in metallurgy and ever closer machining and operating tolerances, aided by the use of robotics, have allowed engines to use thinner and lighter oils. There is less metallic wear while the engines operate and the amount of combustion by products leaking past the piston rings and entering into and contaminating the engine oil has been dramatically reduced. The advances in engine technology coupled with the constant progress of computerized emission controls means a current vehicle emits 95% less pollution than a similar vehicle emitted 2-3 decades ago.

30 years ago there was a single viscosity rating, 30 weight oil. It was the default standard oil that was universally used in most passenger class cars and light trucks. Now there are several multi grade oils such as 10w30, 5w30, 5w20, 0w40 and even a 0w20 being used. Fully synthetic oils have been developed, which aren’t even petroleum based oils. These are designed by engine oil chemists that start as a chemical base that is sulphur and phosphorous free, both of which wear the moving and stationary parts of an engine.

All of this has led the manufacturers toward extending the time and mileage intervals between oil changes in order to reduce the cost of maintenance on vehicles. It also adds to the convenience of owning a vehicle, because there is less time and thought devoted to maintaining the vehicle. Now a vehicle owner can forget about wondering when the next oil change is due or looking at the sticker on the windshield or door jam. The vehicle itself will inform the customer when the next oil change is due. It will even warn the customer with little alerts that are posted in the instrument cluster that say “15% percent of oil life remains”. When the oil change is actually due, the alert will say “0% oil life remains, oil change is due “each time the vehicle is started.



Return to the top of the page
Throttle Body Service

When a Throttle body is serviced, a technician cleans or wipes out the bore of the throttle body and the throttle blade itself. Then he/she checks and adjusts the minimum air rate and checks and adjusts (if needed) the TPS sensor and then performs a computer controlled idle relearn procedure. When this is all done properly, your vehicle should idle as if it was just driven off the showroom floor.

Vehicles with Computer Controlled 'Drive by Wire' Throttle Body can be CAREFULLY wiped clean. Then an Electronic Throttle Body adaption relearn procedure can be performed. This can really improve the smoothness of the idle in all stages of vehicle operation.

As an engine operates, it deposits carbon and sludge from the PCV system into the Throttle body which, after a year or so, will have an effect on how well the vehicle starts, how well it idles cold, warm and especially with different loads applied such as the heater, air conditioning etc. It will also affect how smoothly the vehicle accelerates from a stop.

Another added bonus from this service is that it keeps the computer controlled idle valve clean which, if left uncleaned, will get carboned up to the point where it will have to be replaced and that can cost hundreds of pounds.



Return to the top of the page
Tire Rotation

All 4 tires on a vehicle do not wear at the same rate, and tire rotation will prolong the life of your tires. The tire rotation consists of removing the wheels and moving the front tires to the rear and the rear tires to the front.

Why you need to rotate the tires:

* The front tires will wear differently than the back tires. On front wheel drive vehicles, the front tires are the drive tires and tend to wear out and 'round off' much more quickly than the rear tires. Of course, the opposite is true with a rear wheel drive vehicle. Rotating the tires will even out the wear and make the tires last longer.

* Whether you have a front or rear wheel drive, the front tires will wear differently because they are the ones that steer the vehicle, and thus will wear more quickly.

* When the tires are rotated, they are checked for proper inflation and for any damage that can affect the safety of your vehicle. A tire can be damaged or deteriorating on the inside tread wall and it would never be seen unless it was rotated.

* When the tires are rotated, the brakes and suspension are exposed and can be observed for wear and safety. This is one way to nip a brake problem in its beginning stages before it becomes a safety risk.

* Early signs of alignment wear can be detected during the rotation and can be addressed to prolong the life of the tires.

* At the time of the tire rotation, it is a good idea to have the wheel balance checked.

Exceptions:

* Some all wheel drive (AWD) vehicles have tires that are specially matched and can NOT be rotated.

* Some tires are directional, and can only be installed on the left or right side of the vehicle, These can be rotated but must stay on the correct side of the vehicle. Look for a directional arrow on the tire to determine the correct side.

* Some vehicles have different sized tires in the front and rear, and these cannot be rotated front to rear, but in some cases can be rotated side to side.



Return to the top of the page
Transfer Case Fluid Replacement

Transfer Case fluid lubricates and removes heat from internal components in the Transfer Case

Transfer Case Fluid - much like front or rear differential fluid, needs to be replaced every 30,000 miles due to the degradation of the fluid's lubrication ability and the fact that tiny metal particles will be suspended in the fluid from the normal wear of the gears and bearings. Most Transfer Cases use either a conventional or synthetic gear oil that is designed to with stand the tremendous pressures created by the operation of the gear sets.

It is best to have the vehicle up to normal operating temperature before draining the fluid. Then the technician raises the vehicle on a hoist and removes the Transfer Case drain plug to drain the fluid. Often there is a magnet on the drain plug to catch any suspended metal particles and this should be cleaned off as well. Then the proper amount of new fluid is put into the Transfer Case and the level is checked and verified.

Price range for Labour of Transfer Case Fluid Replacement: £0.00 - £0.00



Return to the top of the page
Transmission Fluid and Filter Replacement

Automatic transmission fluid lubricates and removes heat from internal components in the transmission. The transmission filter removes debris from the transmission fluid.

To replace the automatic transmission filter, the drain plug is removed, allowing the fluid to drain from the transmission. Then the oil pan is removed, and the transmission filter is removed and replaced. Next, the oil pan is cleaned and inspected for debris and then reinstalled. Finally, the transmission is filled with fresh fluid, and the engine is started.

With the engine running and the transmission in "Park," the transmission fluid level is checked on the dipstick. Then the vehicle is driven and the oil level rechecked; more fluid is added is needed,.

The transmission fluid should be replaced at the same time as the filter to avoid contaminating the new filter.
About this Repair: Automatic Transmission Fluid/Filter Change

Recommendations:

* We recommend that you consider changing the transmission fluid every 30,000 miles.

Why this happens:

* After a fluid change, the vehicle should shift smoothly.

Price range for Labour of Transmission Fluid & Filter Replacement: £0.00 - £0.00



Return to the top of the page
Windshield Wiper Entire Blade Replacement

The wiper blade is a rubber blade attached to the end of the wiper arm.

Wiper blades are replaceable and should be replaced when they no longer adequately remove rain or snow from the windshield. Worn out or damaged windshield wiper blades can cause restricted visibility and permanent damage to the windshield.

To replace the wiper blade, it is removed from the wiper arm and replaced with a new blade.

Price range for Labour of Entire Windscreen Wiper Blade Replacement: £0.00 - £0.00



Return to the top of the page
Windshield Wiper Inserts Replacement

Windshield wiper inserts are an economical alternative to replacing the entire wiper blade.

In many cases, the rubber insert can be removed from the wiper blade and replaced. Worn out or damaged windshield wiper blades can cause restricted visibility and permanent damage to the windshield.

Wiper blade replacement should be done on a yearly basis or when the blade starts to fail.

Price range for Labour of Windscreen Wiper Inserts Replacement: £0.00 - £0.00



Return to the top of the page
5,000 Mile Service

The 5,000 mile service is a minor service, and it is the primary service that all other maintenance services are built on.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here

Price range for Minor Servicing: £0.00 - £0.00


Return to the top of the page
6,000 Mile Service

The 6,000 mile service is a minor service, and it is the primary service that all other maintenance services are built on.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle. If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
7,500 Mile Service

The 7,500 mile service is a minor service, and it is the primary service that all other maintenance services are built on.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle. If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
10,000 Mile Service

The 10,000 mile service is a minor service.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your vehicle serviced at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
12,000 Mile Service

The 12,000 mile service is a minor service.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. Some vehicles may require the replacement of the cabin air filter too. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your vehicle serviced at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
15,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Cabin Filter Replacement
Air Filter Replacement
See More

The 15,000 mile service is an intermediate service, and likely the first one for your vehicle.

This service generally involves an oil and filter change, tire rotation, and a safety inspection, as well as possible replacement of the engine air filter and cabin air filter. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here
Possible Repairs Recommended at 15,000 Mile Service

Some vehicles, especially SUVs and Trucks may need brake pad replacement at this service.
learn more about buying brake parts
Warranty Concerns

Problems may be starting to arise as your vehicle starts to get some miles on it, and having warranty repairs is part of vehicle ownership. To learn more about addressing problems with your car, click here

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
18,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Cabin Filter Replacement
Air Filter Replacement
See More

The 18,000 mile service is minor service.

This service generally involves an oil and filter change, tire rotation, and a safety inspection, as well as possible replacement of the engine air filter and sometimes the cabin air filter. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here
Possible Repairs Recommended at 18,000 Mile Service

Some vehicles, especially SUVs and Trucks may need brake pad replacement at this service.
learn more about buying brake parts
Warranty Concerns

Problems may be starting to arise as your vehicle starts to get some miles on it, and having warranty repairs is part of vehicle ownership. To learn more about addressing problems with your car, click here

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
20,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Cabin Filter Replacement

The 20,000 mile service is a minor service.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here
Possible Repairs Needed at the 20,000 Mile Service

It's not uncommon for your vehicle to need a brake pad replacement at this mileage, and on some vehicles the tires may need replacement.

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
22,500 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Cabin Filter Replacement

The 22,500 mile service is a minor service.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here
Possible Repairs Needed at the 22,500 Mile Service

It's not uncommon for your vehicle to need a brake pad replacement at this mileage, and on some vehicles the tires may need replacement.

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
24,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Cabin Filter Replacement

The 24,000 mile service is a minor service. Your next service will be the 30,000 Mile Major Service which can be quite expensive on some vehicles, so be prepared for a big bill next time in the shop.

Fun Fact: You could have driven completely around the earth in approx. 24,000 miles!

This service generally involves an oil and filter change, tire rotation, and a safety inspection, and may include a cabin air filter. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls on your vehicle, go here
Possible Repairs Needed at the 24,000 Mile Service

It's not uncommon for your vehicle to need a brake pad replacement at this mileage, and on some vehicles the tires may need replacement.

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
25,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Cabin Filter Replacement

The 25,000 mile service is a minor service. Your next service will be the 30,000 Mile Major Service which can be quite expensive, so be prepared for a big bill next time in the shop.

Fun Fact: You could have driven completely around the earth in approx. 25,000 miles!

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here
Possible Repairs Needed at the 25,000 Mile Service

It's not uncommon for your vehicle to need a brake pad replacement at this mileage, and on some vehicles the tires may need replacement.

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
30,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Coolant Replacement
Drive Belt Replacement
Auto Transmission Service
Man. Transmission Service
Fuel Filter Replacement
Spark Plug Replacement
Cabin Filter Replacement
Valve Adjustment
Differential Fluid Change

The 30,000 mile service is a major service, and likely the first one for your vehicle. This service may be referred to as a "tune-up". learn more about this term

In addition to all that is performed at the 15,000 Mile Service, the 30,000 mile service is where you will start seeing some of the fluids replaced, such as the brake fluid, engine coolant and transmission fluid, as well as spark plugs, air filters and the fuel filter. A more comprehensive checklist of inspections may also be included. Each shop and vehicle manufacturer may vary the actions performed so be sure to refer to your owner’s manual.

If you have your service performed at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, click here

Possible Repairs Needed at the 30,000 Mile Service

It's not uncommon for your vehicle to need a brake pad replacement at this mileage, and on some vehicles the tires may need replacement.
Warranty Concerns

Problems may be starting to arise as your vehicle starts to get some miles on it, and having warranty repairs is part of vehicle ownership. To learn more about addressing problems with your car, click here

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
35,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Coolant Replacement
Drive Belt Replacement
Auto Transmission Service
Cabin Filter Replacement
See More

The 35,000 mile service is an minor service.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your vehicle serviced at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, go here
Possible Repairs Needed at the 35,000 Mile Service

It's not uncommon for your vehicle to need a brake pad replacement at this mileage, and on some vehicles the tires may need replacement.
Warranty Concerns

Problems may be starting to arise as the mileage on your vehicle increases, and having warranty repairs is part of vehicle ownership.

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
36,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Coolant Replacement
Drive Belt Replacement
Auto Transmission Service
Cabin Filter Replacement

The 36,000 mile service is a minor service. If you missed your 30,000 Mile Service, consider having that service performed now.

This service generally involves an oil and filter change, tire rotation, and a safety inspection, and may include a cabin air filter. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your service at the dealership, have them check and perform any recalls on the vehicle. To check for recalls on your vehicle, go here
Possible Repairs Needed at the 36,000 Mile Service

It's not uncommon for your vehicle to need a brake pad replacement at this mileage, and on some vehicles the tires may need replacement.

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
37,500 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Coolant Replacement
Drive Belt Replacement
Auto Transmission Service
Cabin Filter Replacement

The 37,500 mile service is an minor service.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.

If you have your vehicle serviced at the dealership, have them check and perform any recalls on the vehicle. To check for recalls, go here
Possible Repairs Needed at the 37,500 Mile Service

It's not uncommon for your vehicle to need a brake pad replacement at this mileage, and on some vehicles the tires may need replacement.
Warranty Concerns

Problems may be starting to arise as the mileage on your vehicle increases, and having warranty repairs is part of vehicle ownership.

Price range for Minor Servicing: £0.00 - £0.00



Return to the top of the page
40,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Coolant Replacement
Drive Belt Replacement
Auto Transmission Service
Cabin Filter Replacement
Timing Belt Replacement
See More

The 40,000 mile service is a minor service.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.
Warranty Concerns

On some vehicles you are nearing the end of your warranty period and you should pay close attention to the operation of your vehicle and have any issues addressed while the warranty is still valid. If you have your service performed at a dealership, have them check and perform any open recalls on your vehicle. To check for recalls, click here
Possible Repairs Needed at the 40,000 Mile Service

It's not uncommon on some vehicles to start seeing the wear and tear items like the Drive Belts and Hoses, Motor Mounts and Suspension Bushings starting to show signs of wear. Oil leaks may start to appear as well. Check out the Common Problems page for your vehicle so you can have some idea as to what the future may hold for you and your vehicle. go here

Price range for Minor Servicing: £0.00 - £0.00


Return to the top of the page
42,000 Mile Service

Related Services & Repairs
Tire Replacement
Brake Pad Replacement
Brake Pad/Rotor Change
Coolant Replacement
Drive Belt Replacement
Auto Transmission Service
Cabin Filter Replacement
Timing Belt Replacement
See More

The 42,000 mile service is a minor service.

This service generally involves an oil and filter change, tire rotation, and a safety inspection. While changing the oil, the mechanic will be performing visual inspections of the brakes, belts and hoses, inspecting for any fluid leaks, listening for any abnormal noises, and paying attention to any irregularities in the operation of the vehicle.
Warranty Concerns

On some vehicles you are nearing the end of your warranty period and you should pay close attention to the operation of your vehicle and have any issues addressed while the warranty is still valid. If you have your service performed at a dealership, have them check and perform any open recalls on your vehicle. To chec