Checking components
In order for the variable valve timing control to function correctly, the correct grade of engine oil must be used. The oil must be clean and the oil pressure must be correct.
Check the level and quality of the engine oil. Check for contaminants in particular.
Check the engine oil pressure.
Remedy as necessary.
If no fault is found in the above fault tracing and the adaptation value is too low (lower than -8°) when the engine is at operating temperature, the cause of the fault is probably one of the following:
- Camshaft belt incorrectly seated
- Incorrect basic setting of the timing belt
- Faulty camshaft reset valve (the slide in the valve has stuck).
HINT: Try adjusting the basic setting of the camshaft if no fault is found during the above fault-tracing. Then read off the adaptation value for the camshaft with the engine idling and at operating temperature. The value must be between -8° and +8°. If the adaptation value is incorrect when the basic setting of the camshaft is correct, try cleaning the camshaft reset valve.
The camshafts must be adjusted using the adjustment tool for the camshafts and crankshaft in the prescribed manner.
Try a new camshaft reset valve if the above fault-tracing does not solve the fault.
Remedy as necessary.
HINT: The fault may also be caused by a defective variable valve timing unit. The variable valve timing unit may be damaged if the above fault-tracing and corrective action do not remedy the fault.
Other information:
- See VVT solenoid, inspection and cleaning
- See Checking oil pressure
- See Variable valve timing solenoid, replacing
- To adjust the camshaft position (CMP), see: Camshaft seal/variable valve timing (VVT) unit, replacing
- Continue
Refer to Verification