92 grand am IAC problem

Hi i have a 92 grand am 2.3l automatic. When i drive the car the check engine light comes on and the car idle surges coming to a stop and sometimes stalls the engine. When scanned it comes up with a possible IAC problem. Ive replaced the IAC and its still doing the same thing. Is there something else that can cause this? Any help would be greatly appreciated. Thank you.