Can't Find Idle
 

Alright I have been trying to fix this problem for months. Whenever my car gets hot and has been driven for about 30 minutes whenever I stop at a light and take the car outta gear it idles up to about 1400 rpm's then it goes down to 700 once it hits 700 it jumps up to 1000 and it will do that forever until you start moving again. It will also do it in gear but not as much, I was thinking vacuum leak but I can't find one anywhere. I was also thinking maybe it could be the EGR 0-ring. I tried advanced auto and couldn't find one so does anyone have the part number for that. Does anyone else have any ideas on what could cause this. If i reset my ECM it gets really bad, so thats not it. I have tried taping on the ecm to detect any difference in operation and there are none so that is good. Im stumped please help a bro out. :usa:

did you take the screen out of the Mass air meter? I know a friend of mine did that to his Ls1 along with the larger composite ends and the idle was all over the place. He ended up buying a completely stock one and bolted it on and it idled great again.

Could be a vacuum leak. Did you try spraying some carb cleaner around the EGR O-ring?

Hmm whats carb cleaner going to do. Should it bubble or something to indicate a leak? I never tried that before is there something I should look for. And also does anyone have a P# for that O-Ring I can't seem to find one at Advanced.

I know you tried resetting the pcm.But my car did the very same thing when I put on the bbk80mm tb .I ended up disconnecting the battery over night and when I started it back up in the morning they(bbk) told me not to touch the gas pedal until the car reached normal operating range and that fixed my problem.They (bbk) said the computer had to relearn how to idle. Hope this helps.

I think carb cleaner will get sucked into the leak if there is one and th emotor will rev up slightly. Propane will do the same thing.

Well that would be useless because it revs up anyways when it is warm and won't do it when it is cold so that kinda sounds like something is expanding when it gets hot causing a leak. The problem is nothing that would cause a leak really expands so im stumped. Any other options?