Generally when a DC motor is spent, it shows an infinite resistance, or a direct short. My IAC tests 58 ohms across both sets of terminals, but I'm at whit's end here.

I once again put the ECM into diagnostic mode and tested the 4 harness terminals. Like usual, all 4 make the test light blink rapidly as it should. The IAC has *GOT* to be getting the proper signals. The IAC is brand new, but I'm wondering if it isn't defective anyway.

Over the weekend I replaced the plastic connector (original pins) to ensure that the plug is seating properly. The IAC counts stayed pegged at 160 the whole time tonight while the car ran. I purposely dropped the idle WAY below the desired idle (which should cause the IAC to open) and it made no difference. Unplugging the IAC causes no change in idle at all.

So anyway... can the IAC test ok and still be faulty?

 

Thanks for all the help.

I threw another new IAC on there (the one I took off isn't even dirty yet), and surprise surprise, it didn't change anything.

I started the car and it wouldn't maintain the desired idle. Once it warmed up, it would idle ok. IAC counts were steady at 151. I raised the idle screw a little bit and the iac counts slowly went down.... and down.... and down until finally it parked at 0. I brought the idle back down a little bit, and the IAC counts began to go up. At around 35 the fan kicked on and the IAC counts went up to around 50, but seemed to keep rising... then the POS scan tool lost communication with my ALDL and wouldn't work the rest of the night.

Anybody have any ideas at all here?