What up I'm having a problem with my 2000 mustang GT. I just got back from overseas and my car was sitting for about 8 years it was started every once and a while but was not took care of like it should have been. I have been getting it back together and I can't seem to get rid of this high hanging idle (1050-1200). While driving I let the gas pedal go its stays at 2000 (4sec) them drops to 1500(3sec)then to the high idle. I have check for vacuum leaks Cleaned the MAF sensor Cleaned the plenum Cleaned the throttle body Cleaned the EGR valve Replaced the EGR vacuum solenoid Replaced the air filter Replaced IAC If you can think of anything that would be great and thanks you ahead of time.