If you have removed the IAC from the housing, don't disassemble it.
Spray some rust penetrant into the [ports and let it soak for a while. Use a feeler and gently pry at the vale to make it open. DO NOT force as it will damage the valve. Try to slowly work the valve loose. It might take some time.
Use carb cleaner to clean what ever dirt inside the chamber and after job is done, make sure the valve moves easily with minimal force and befor installation back to throttle body, spray some rust penetrant into the chamber again to lubricate the bearings. Let it soak for a while as the 2 bearings would seize if it is not lubricated.
Thursday, March 15th, 2012 AT 2:12 PM