Diagnostic help
The engine's fuel requirement is 25% less under partial load than that which the control module has calculated using information from the mass air flow sensor.
Fault diagnosis first determines if the pressure sensors indicate about the same value with the ignition ON, as the mass air flow sensor is then compared with the intake air pressure. If the pressure sensors are OK but the mass air flow sensor value is not correct, then air leaks between the compressor and the throttle are checked for first and then the mass air flow sensor is changed.
If the air quantity is OK, then the fuel supply is checked, i.e. pressure, response, pump flow and finally the injectors.
Functions in the diagnostic tool related to the fault:
- Diagnostic status for the diagnosis.
- Multiplicative Adaptation, unit %
- Closed loop, unit %.
- Purge Adaptation, unit %.
- Air mass deviation from calculated, unit %.
For more information, see FAULT HANDLING III, OTHER EMISSION-RELATED COMPONENTS AND FUNCTION ).