Need Help.......3.4 idle way too high

[94bird]

Lately my car is idling really high at startup, around 2200 RPM's. Once it warms up it drops to about 12-1300 which is still too high.
I had this problem about 6 months ago and I replaced the IAC (idle air controller) and the problem was gone, car idled normally. Now all of a sudden the problem is back.
I went out and got another IAC but it didn't help. I don't have a scanner to see if I'm getting anny trouble codes and the SES light has not come on.
Does anybody know what could be causing this or how to fix it?

edit: I reset the PCM and the idle went back to normal, but once I turn the car off and restart it the problem returns.
I have also checked for a vaccum(sp?) leak and a sticking throttle linkage and haven't found either one.

[ October 04, 2002: Message edited by: 94bird ]</p>

[Tiago]

check for vacuum leaks, also might be a bad TPS sensor.

[Harry94]

I had an idling problem once. I could figure out what it was for the longest. It was on and off. Turns out it was a short in the spark plug wires and the spark plugs needed changing.

[southern94]

i replaced my IAC sensor and my TPS when i had that prob and nothing fixed it so i said screw it. it kept happening on and off i even put a diff tb on there thinking there was a chip in the throttle plate or something and one day it just stopped lol [img]graemlins/fluffy.gif[/img]

[mr_man]

i'm having this same problem. except this morning i started my car and it was idling about 2200 then i went inside and when i came back out it was at about 2700. It only seems to idle high on a cooled down engine, when at a stop driving it idles at about 1200. Where is the IAC?

[MustangEater8251]

Check yor a vacuum leak, most likely, in the t-fitting on top of the motor.

basically go to the TB, then about 6 in. behind it is a rubber, probable now hard as a rock and crumbling pice of t-fitting there. Check that out to see if its leaking there.

[94bird]

I really don't think it's a vacuum leak because when I reset the PCM the car goes back to normal, if there was a leak it would idle rough all the time.
How do I check the TPS?

[94bird]

It's the weirdest thing all of a sudden it went back to normal.
I got in my car Sat. night to go out and it was fine......idle at about 600 rpm .
I'd still like to know what was causing it, but I'm glad it's gone. :D [img]graemlins/burnout.gif[/img]