I would love to look at the waveforms going to the IACV, but it's hard gaining access to the pins. I suppose I could nick the wires going to it and clip the scope there to see what's going on. I'd be curious to know if the ECU is trying to bring the idle down.
BTW, I did jumper the diagnostic pins and the idle did not go down all the way. You could here it cycling somewhat. The check engine light blinked the 'all is normal' code.
I do have one question or concern -- I pried the black cap off the idle adjustment screw. It was totally bottomed out. I then put my finger over the IACV port and the idle dropped to about 900 RPM. I've had the TPS out for cleaning and there's nothing hanging up the butterfly. It closes all the way. My question is should the engine be able to idle with the idle adjust fully bottomed and the IACV port blocked? (I already pinching close all the vacuum lines to the manifold include the A/C idle up. None of them made any difference.) I'm wondering if there's another idle bypass I'm not seeing. I'm going to pull the TPS again tomorrow for a closer look.