"Darn the bad luck". Then you're going to need a scanner to see what the Engine Computer is trying to do.
One thing you can try is to unplug the IAC motor while the engine is running, then you can stop the engine and pull the motor out to see where the pintle valve is positioned. You have to do that before you stop the engine because as soon as you turn the ignition switch off, the valve will retract in preparation for the idle flare-up at the next start.
You can also pull the valve out to extend it. It will pull real hard but it can be done. Reinstall it that way but don't plug it in. Start the engine, then see how fast it idles. If there is no vacuum leak, you should have to hold the gas pedal down just a little to keep the engine running. If the idle speed is still too high, there has to be unmetered air sneaking in. Try pinching off vacuum hoses, especially the hoses to the brake booster and the cruise control servo.
Don't overlook the coolant temperature sensor and the intake air temperature sensor. That one sits in the fresh air tube near the right hood hinge.
Sorry I overlooked your original comment about no vacuum leaks.
Tuesday, February 8th, 2011 AT 4:14 AM