Eratic Idle

[Ronnie01]

Hey guys, this question is about my 92 TSI FWD. When i go to start it in the mornings when its cold, it will idle about 1.5k or so or a lil higher and then fall down after a lil while, i know thats normal. What isnt is when i go to back it up or something when its still warming up, the idle fluctuates between 1000rpms and 2500rpms's and jus goes back and forth like that for a while. Anyone know whats causing it? Also, instead of making another thread i'll jus ask on this one, i jus got this car and the guy before me swapped in a 2g manifold for no cracking i suppose, but anyway there is a probe coming out of it, i would say its a 02 but its small, its coming right out the top of mani an i followed the wire but its not plugged into anything, what exactly is it? THanks guys

 

[majik2k5]

I had an idle problem similar to that. It turned out to be a vaccum leak in my car. Simple fix. A friend just sprayed some stuff on the stock intercooler piping and we followed it to where the leak was. As for the probe, I've seen a pyrometer gauge ran like that before at a DSM show I went to. But I'm not 100% on how they actually are ran, so don't hold me to it.

 

[wkd4g63]

coud be one of 3 things,

1- vacuum leak

2- Bad ISC motor

3- Air pocket in the coolant line


My suggestion would be to pressure test the system, clean the tb and isc motor , and burp the coolant system , between that it will take care of general maintainence and possibly fix your problem.


-Joe @ extreme

 

[aadperformance]

and yes that would be a probe for an EGT guage