Rough, Unstable Idle and/or Stalling

WARNING: This page is about a different variant/trim than selected.

Engine idle speed may be unstable or the engine may stall if the ECM has learned an incorrect idle/airflow compensation value. A DTC may also set. Observe the scan tool Throttle Body Idle Airflow Compensation parameter. A value greater than 90% may indicate an excessive accumulation of deposits in the throttle bore. If the throttle body needs cleaning, refer to Throttle Body Inspection and Cleaning .
The actions listed below may also cause the ECM to learn an incorrect idle value.
- The engine control module has been replaced
- The throttle body has been replaced
- The throttle body has been cleaned but the idle learn procedure was not performed after completing the cleaning
- The air induction system was leaking, allowing non-metered air to enter the combustion chamber. The leak was repaired but the idle learn procedure was not performed after repairing the leak
  If any of the actions listed above have occurred, the Q38 THROTTLE BODY: THROTTLE/IDLE LEARN procedure must be performed.
Inspect the engine mounts for looseness, wear and damage.