I can now cruise under 30 mph in third gear without it bucking. I had not been able to do so before. I do not know what the throttle setting had to do with it, but I like it.
I pretty much have the same issue. It doesn't do fast idle on cold starts like it should. And I know my IAC is working because when I unplug it, idle goes down so low that it almost kills the engine. And as soon as I plug it back up it kicks back up to roughly 800 RPM.
But I can hop in my '92 Bronco and every time I start it, no matter if it's at operating temp or dead ass cold, it'll do fast idle and depending on temperature it'll only last for a few seconds, or over 30 (when it's cold as hell)
I fixed this issue without even trying to fix it. I had an intake gasket leak that was causing a popping through the passenger side exhaust and I had coolant getting in to my oil. After putting on new gaskets, it does fast idle as it should. Weird.