The idle seems pretty high on my 90 tgp, its got a reburned chip from Skalor. the car wasnt to just accelerate on its own, i have to press the brakes to go anything under 10-15 mph. it idles at like 1200-1400. warm, and if the a/c comes on, it jumps to nearly 2k! and then slowly goes down to 1200-1400 again. This is kind of annoying, any ideas? Iv leaned the IAC before and no difference.

Try doing an idle relearn- it helped my idle a lot.

Did you do anything other than the chip? Did you hit a vacuum line? Did it do this immediately after you installed the chip or did it take a little time before it did this?

its always done this since i bought it 2 years ago, lol. Iv checked and fixed 2 vacuum leaks. I might try another idle relearn, because i disconnnected the battery a few weeks ago and didnt bother. But i notice when u start it warm the idle spikes up to 2k imeidiatly and then levels off down to 1100-1200. The car runs fantastic otherwise.

Quote from: Prospeeder on March 02, 2007, 11:58:48 PM
its always done this since i bought it 2 years ago, lol. Iv checked and fixed 2 vacuum leaks. I might try another idle relearn, because i disconnnected the battery a few weeks ago and didnt bother. But i notice when u start it warm the idle spikes up to 2k imeidiatly and then levels off down to 1100-1200. The car runs fantastic otherwise.

Mine used to do the exact same thing: I fixed two vacuum leaks, cleaned my TB, all of its passages and the whole idle control assembly, reassembled it all, did an idle relearn, and now it idles perfectly.  Try that. ;)

A high idle is one of two things.

The chip is telling it to idle that high.

There is a vacuum leak that the chip can not compensate for and it sits high.

If you have a diag tool to see what the desired idle RPM is or what the IAC steps are sitting at you can easily determine which is the cause.

I think 90% of the high idle complaints I have seen on here have been narrowed down to a vacuum leak. Trust me...it does not need to be big for a high idle to be present. Get out the can of carb cleaner and start tracking it down. ;)

Just a tip- I found a broken vac line by my battery- it is the one that goes to the vac ball, and it broke in that tight area somehow...  After I fixed it, it ran much better- I was really surprised at the difference a bad line makes.

TGP Nick. I had the same problem. Exact spot. It's probably common with these cars.

when I idle my TGP with the datalogger running the RPM reading on the laptop is always about 200 lower than what the tach reads, I was advised of this by Jeff M long ago and did verify it for myself.  I would not be surprised to find that you have at least one faulty injector, because if it didn't do that right off when you swapped the chip, well it's something else.  You did get hit in the front end, I would advise checking the connection at the vacuum canister underneath the drivers side front of the vehicle. 

The relearn helped abit. I just had the bumper off and had the vacuum ball off, but it looked ok, ill check that hose. and hopefully hook it up to a scanner

I was told by a cluster reman company that the GM tolerance for RPM scale is + or - 500 RPM. The datalogger can not lie so trust that more than the dash. ;)

ohh well my cross overs leaking pretty good, i seafoamed it, and smoke poured off the cross over. sooo ill be investing in one of those soon....

I read in my TGP factory Service Manual to use a Tech I scan tool to do the idle learn but it also stated how to do it without the tool, but I can't find it again. So how are you doing the idle learn without the scan tool? Thanks...T :dunno:

Well could this really be the cross over? cause i start it, and the idle flies up to almost 2k for like 10-15 seconds and then suddlenly just drops to 1000 ish. Iv done 2 idle relearns, its not helping, and theres no leaks.

I have seen this type of thread over and over on the turbo dodge site and over and over it turns out to be a vacuum leak the guy just couldn't find. I have also seen idle speed motors stick and not respond to cleaning but not near as much as a leak. We just had an older chevy pick up with throttle body injection have a sticking motor. It would start and run high it would come down but not low enough. We found a leaking throttle body gasket and replaced it. It then would start high but not as much but would settle down to normal after a while. Tapping on the speed motor with a small hammer would help bring down the idle. The guy working on it broke it while cleaning but a new one did fix it. So it had both issues.
Tim