I have an 03 gt automatic. When I turn the car on it idles around 1k rpms and when I put it in gear it jumps up to around 2.5k rpms. I can drive for a minute or two but then it shuts off. When I crank it back up it runs fine. If I get down on it though it will start idling high, so then I put it in neutral to turn it off and back on. Once again it runs fine after that. I have changed out the IAC, PCV, Throttle position sensor, and I've cleaned the throttle body. If you have any suggestions or solutions please let me know!