Just two days ago my 2001 V6 Mustang has had an idle problem. When I start the car it sits at about 2-2.5k rpms. When I shift it will sit there as well. But if I barely press on the gas they will start lower and rise. But when the clutch is in, the rpms wont go to 0 like they should.

I was told by a former ford mechanic that it was the IAC motor. So I cleaned the carbon out of that to try to get it to last a little longer. That didn't work so I bought a new one and installed it and my problem isn't any better.

So just wondering of any ideas on what it could be. Only thing I can think of is the throttle line catching on something

 

start looking for broken vacuum lines