My 88' Mustang 2.3L (Non-Turbo) has been having a weird issue (Engine possibly). I can start the car and idle it as long as I want with no problem, I can give it gas and keep the revs up with no problem, but as soon as I take the gas off and it goes to return to idle...the engine stalls out. I've replaced the TPS, Sparks, Fuel Pump, and a few other things that have nothing to do with this problem.

Anyone have any idea what might be causing this? I don't really feel like paying a shop to tell me what the problem is because I'll be doing the work myself. I'm a mechanic but don't have the tools right now to diagnose the problem.

Any ideas or suggestions on what to check next would be awesome!

Thanks.

 

IAC motor?