You probably want to try cleaning the AIC valve on the bottom of the throttle body. unbolt the TB, unplug AIC & remove to clean. It's a small barrel shaped valve with a cutout that turns to adjust airflow at idle. Clean AFM also, be sure to use electric parts cleaner.
X 2
It's definately the IAC valve on the bottom of the throttle body. I've had very little luck cleaning them out though - they always gum up again within the next 10k miles. Personally, I'd replace it if you can afford one. Get the gasket for it too. While you got the throttle body off, clean it out too, but take the TPS off before you do because brake cleaner and carbon run-off kills those things.
