ApocalypseHoboken

Hey guys, I'm still rather new to this Mustang thing... I have an 87 GT 5 speed with a mild cam, and a fenderwall CAI. My problem has been with the idle. When I bought the car last fall it was fine. I put it in storage for the winter and now after doing that I've run into this damn idle problem. The idle isn't loping or anything.... It's sticking at 1500-2000 rpm.

It started out as a problem that would occur after I drove the car for about 20 minutes or after spending a few minutes in 5th gear and then coming to a stop. Then I noticed it happened a lot when I spent time in heavy traffic. The car would return to idle at 800-900 rpm just fine and then after a while i'd come to a stop and it would first want to idle around 1100. Then the next time I'd come to a stop it would idle around 1300 progressing it's way with each stop towards that 1500 mark and staying there.

I recently changed the gears to 3:73 and for some reason after the gear swap the problem got even worse. I took some suggestions and changed the IAC which didn't really help too much. I did however notice that if I really feathered the gas while driving that it idled okay; but if I put the RPM above 2000 that seemed to instantly trigger a problem of not wanting to return to normal idle.

Today I bought a TPS thinking that could be the problem. I threw it on and now the car doesn't want to idle normal at all. The WHOLE time it wants to idle around at least 1500 and after driving for a few wants to idle around 2000!

Can anyone tell me what is wrong here?

Thanks guys...

mattdel

idle screw could be set like that because of the SD and cam

92GreyGT

Sounds to me like you have a vacuum leak.

capri debris

Buy or borrow a scanner and check for codes. That is ALWAYS the first place to start with a problem in my book.