Cold Start Problems
In time the coolant temperature sensor corrodes inside the cylinder head. This will interfere with the resistance and signal which will make the ECU think the water temperature is higher than it actually is. As such no enrichment of the mixture takes place.
Solution
Fitting a new temperature sender should rectify this fault.
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Symptoms of a Camshaft Sensor
The Top Dead Centre (TDC) sensor tells the Engine Control Unit (ECU) where top dead centre is on the engine.
Symptoms
1) Engine cranks but won’t start
2) Engine starts and begins to idle roughly with the EML illuminated
3) Engine won't kick over when it is cranked
4) Engine fails to start after a hot run, i.e. won’t start until cooler
Solution
The sensor is located under the spark plug cover on the 16v engines and it is secured via a 10mm bolt situated between the two pullys, so removeal oif the cambelt cover is needed.
Remove sensor and wipe it with some contact cleaner to see if this rectifies the fault. If not a replacement is required.
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Low Idle Speed, High Idle Speed or Stalling at Junctions
The culprit will probably be the Idle Control Valve (ICV) which is located on the top of the inlet manifold. The ICV acts as a gate allowing varying amounts of air into the engine. However they are known to stick. Then they either let too much air into the engine, possibly causing high revs, or not enough starving it of air and causing the engine to almost or actually cut out.
Solution
Remove the wiring connector and three bolts that hold the ICV in place. Liberally spray it with carb cleaner using a small brush to remove any deposits. A new O-ring will be required for reinstallation.
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Misfires & Hesitation
It is probable that the coil pack has started to fail.
Solution
Unfortunately the only certain way to rectify this is to purchase a new coil pack, but check the condition of your plug first.
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Engine Revs Not Exceeding 4000rpm
The Air Flow Meter (AFM) measure the amount of air passing into the engine from which the computer can work out how much fuel to add to get the perfect mixture for that specific throttle opening, the computer does this by referring to a map in its memory.
Solution
Try cleaning the Mass Air Flow (MAF) sensor. This is located within the air ducting just after the air filter. Undo the electrical connector and withdraw the MAF sensor. Clean with carb cleaner then brush softly. It is important to check all vacuum pipes for signs of splitting or perishing.
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Intermittent, Delayed Starting or Clicking Sound
These symptoms will be caused by faulty or badly corroded terminals on the starter motor or solenoid. In a worst case scenario the motor itself may have failed.
Solution
Remove the electrical connectors and clean them with a brass wire brush removing any corrosion present. Apply something like Vaseline and refit. If this fails, remove starter motor and replace.
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Air Bag and EML Illuminated
Solution
Under each of the front seats in the area of the seatbelt pretensioners there will be a block connector. With the ignition turned off remove both and refit them firmly as they have a tendency to come loose more so on a 3 door. If the light is still on, remove again and spray with contact cleaner. Finally tape the conectors together to hold the two halves in place.
Make sure the ignition has been switch off for at least 10 minutes before you attempts the procedure, to be extra safe the SRS fuse can be removed if you wish.
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The above solutions are not guaranteed to work 100% but are based on information that has been correlated over a number of years. If you do not find that a solution works, you are advised to consult a good independent garage.
Disclaimer: Mk3OC will not take any responsiablity or blame with regards to damage or loss caused should you try any of the above it is ment as a information thread only.
The above text belongs to the author of this thread and MK3OC you are not authorised to copy and paste this information without prior approval.
In time the coolant temperature sensor corrodes inside the cylinder head. This will interfere with the resistance and signal which will make the ECU think the water temperature is higher than it actually is. As such no enrichment of the mixture takes place.
Solution
Fitting a new temperature sender should rectify this fault.
--------------------------------------------------------------------------------------------------------
Symptoms of a Camshaft Sensor
The Top Dead Centre (TDC) sensor tells the Engine Control Unit (ECU) where top dead centre is on the engine.
Symptoms
1) Engine cranks but won’t start
2) Engine starts and begins to idle roughly with the EML illuminated
3) Engine won't kick over when it is cranked
4) Engine fails to start after a hot run, i.e. won’t start until cooler
Solution
The sensor is located under the spark plug cover on the 16v engines and it is secured via a 10mm bolt situated between the two pullys, so removeal oif the cambelt cover is needed.
Remove sensor and wipe it with some contact cleaner to see if this rectifies the fault. If not a replacement is required.
--------------------------------------------------------------------------------------------------------
Low Idle Speed, High Idle Speed or Stalling at Junctions
The culprit will probably be the Idle Control Valve (ICV) which is located on the top of the inlet manifold. The ICV acts as a gate allowing varying amounts of air into the engine. However they are known to stick. Then they either let too much air into the engine, possibly causing high revs, or not enough starving it of air and causing the engine to almost or actually cut out.
Solution
Remove the wiring connector and three bolts that hold the ICV in place. Liberally spray it with carb cleaner using a small brush to remove any deposits. A new O-ring will be required for reinstallation.
--------------------------------------------------------------------------------------------------------
Misfires & Hesitation
It is probable that the coil pack has started to fail.
Solution
Unfortunately the only certain way to rectify this is to purchase a new coil pack, but check the condition of your plug first.
--------------------------------------------------------------------------------------------------------
Engine Revs Not Exceeding 4000rpm
The Air Flow Meter (AFM) measure the amount of air passing into the engine from which the computer can work out how much fuel to add to get the perfect mixture for that specific throttle opening, the computer does this by referring to a map in its memory.
Solution
Try cleaning the Mass Air Flow (MAF) sensor. This is located within the air ducting just after the air filter. Undo the electrical connector and withdraw the MAF sensor. Clean with carb cleaner then brush softly. It is important to check all vacuum pipes for signs of splitting or perishing.
--------------------------------------------------------------------------------------------------------
Intermittent, Delayed Starting or Clicking Sound
These symptoms will be caused by faulty or badly corroded terminals on the starter motor or solenoid. In a worst case scenario the motor itself may have failed.
Solution
Remove the electrical connectors and clean them with a brass wire brush removing any corrosion present. Apply something like Vaseline and refit. If this fails, remove starter motor and replace.
--------------------------------------------------------------------------------------------------------
Air Bag and EML Illuminated
Solution
Under each of the front seats in the area of the seatbelt pretensioners there will be a block connector. With the ignition turned off remove both and refit them firmly as they have a tendency to come loose more so on a 3 door. If the light is still on, remove again and spray with contact cleaner. Finally tape the conectors together to hold the two halves in place.
Make sure the ignition has been switch off for at least 10 minutes before you attempts the procedure, to be extra safe the SRS fuse can be removed if you wish.
--------------------------------------------------------------------------------------------------------
The above solutions are not guaranteed to work 100% but are based on information that has been correlated over a number of years. If you do not find that a solution works, you are advised to consult a good independent garage.
Disclaimer: Mk3OC will not take any responsiablity or blame with regards to damage or loss caused should you try any of the above it is ment as a information thread only.
The above text belongs to the author of this thread and MK3OC you are not authorised to copy and paste this information without prior approval.
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