I have starting and idling problems, like most others have experienced. I won't go into detail about all the symptoms, except to say that they all point to the IAC. The car, by the way, is an 82 K-JET.

But I don't think the problem is the IAC itself. I replaced it with a good junkyard unit, which only seemed to eliminate the problem for a few days or weeks.

I've precisely adjusted the TPS so it clicks just before the throttle is completely closed (can I get more precise?).

Where else can I look? Yes, I look for vacuum leaks all the time. I've replaced two leaky hoses, but that hasn't solved the problem.

Could it be wiring? The problem is NOT intermittent. So if there is a wiring problem, it's not just a touchy connection.

I've cleaned by IAC out with throttle body cleaner several times. It hasn't helped, but now I'm wondering if the cleaner could have gotten into the motor part of the IAC and caused problems?

Where else can I look? This thing has been stumping me for 6 months now. Oh, one more thing: turning on the A/C compressor completely eliminates the problem.