While the problem is occurring, keep the engine running by giving it just enough throttle to keep it from stalling. With the Idle Air Control (IAC) valve connected, monitor the voltage across the 2 wires at the IAC valve connector. The higher the voltage, the harder the Powertrain Control Module (PCM) is trying to raise the idle. Expect more than 4 volts if the idle is lower than normal. Then, with the engine running at a low idle speed, unplug the connector, and if the RPM does not drop when the connector is unplugged, replace the IAC valve.
Sunday, October 6th, 2013 AT 5:55 PM