Idle Air Control (IAC) Valve

Idle Air Control (IAC) Valve




The Tech 2 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 vacuum leak.

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

For other possible causes of idle problems, refer to Rough, Unstable, or Incorrect Idle, Stalling in Diagnosis by Symptom.
Symptom Related Diagnostic Procedures