Monitor Description
The ECM monitors the idle speed and idle air flow volume to conduct Idle Speed Control (ISC). The ECM determines that the idle speed control system is malfunctioning if the following conditions are met:
- The learned idle air flow volume remains at the maximum or minimum 5 seconds during a driving cycle.
- After driving at 6 mph (10 km/h) or more, the actual engine idle speed varies from the target idle speed by between 100 RPM and 200 RPM, 5 times or more during a driving cycle.
- Example:
- If the actual idle speed varies from the target idle speed by more than 200 RPM* 5 times during a driving cycle, the ECM illuminates the MIL and sets the DTC.
HINT:
*: Threshold idle speed varies with engine load.