Idle air control motor is on the throttle body.

Scotchbrite and some throttle body cleaner will do wonders. Just make sure to build a little engine heat before attempting to unscrew the loctited IAC screws so you don't wring one off. A bit of engine heat should soften the loctite nicely.

Also. Make sure your EGR valve is not hanging open at idle. I know that made mine really unpredictable.