Well I thought my IAC was going out on me again because I was getting all the same signs as I did last time it died (car starts, rpms go up as normal, but instead of stopping at idle speed rpm's fall until the car cuts off). How do I know its not the IAC? Because I just replaced it yesterday. Now I did just have a MAC PC (catless) and A/T c/b installed about a month ago. Could this have something to do with it? What else could cause the car to not idle and just die like that? Any help is appreciated.