Symptom Definition

Engine starts but will not run at idle. Engine will run if accelerator is held at part throttle.

Possible Cause & Correction Check the following:

• Problem is most likely in Idle Air Control (IAC) system. See DIAGNOSTIC AIDS in CODE 35 chart in appropriate TESTS W/CODES article.
• Check EGR system.
• Check Park/Neutral switch.
• Disconnect MAP sensor. If condition is corrected, replace sensor.