Idle Air Control (IAC) Valve

The scan tool displays the IAC pintle position in counts. A count of 0 indicates the PCM is commanding the IAC pintle to be driven all the way into a fully-seated position. This is usually caused by a large vacuum leak.

The higher the number of counts, the more air is being commanded to bypass the throttle blade. Refer to IAC System Check in order to diagnose the IAC system.

Refer to Diagnosis by Symptoms, Symptom Diagnostic Procedures - Rough, Unstable, or Incorrect Idle, Stalling for other possible causes of idle problems. Testing and Inspection