Checking System

Checking System







HINT: If the fuel adaptations indicate too rich fuel/air mixture (adaptation value below 1.0) in several adaptation ranges, this indicates a fuel malfunction, e.g., too high fuel pressure. To find the problem, proceed as follows:

- Check that the oil level is between the minimum and maximum markings
- Check the induction system for clogs and loose components (such as a loose air guide in the air filter holder).

- HINT: The adaptations may show rich if several cold starts have been performed with short subsequent driving time, e.g., moving of vehicles, and the engine oil has thus been contaminated by gasoline. This affect on the adaptations disappears after a period of driving due to combustion of the fuel vapors by the engine.

- Check the EVAP-valve for leakage.

HINT: A valve that does not seal constantly leaks fuel vapors, which thus affect the adaptations.

- Engine running.
- Check fuel pressure for high fuel pressure.
- Ignition on
- Check residual pressure for too low residual pressure.

Remedy as necessary.

HINT: Normal fuel pressure at idle and warm engine shall be approx. 480 kPa. The residual pressure when the engine is off and the ignition is on shall be approx. 100 kPa lower than during idle. If the residual pressure is too low, one malfunction cause may be leaking (non-sealing) injectors, for example.

Other Information
- Air leaks in the intake system, checking

Continue: Refer to Checking Mass Air Flow Sensor. Checking Mass Air Flow Sensor