1G Idle problem

[xander061]

i hav a 91 talon tsi fwd 5 speed and when i start up the car it idles up and then trys to die but if i tap the gas pedal for a bit it idles up around 3-4k for a few sec then eventually drops down to 500rpm. Once you start driving it its fine it just does that at start up and sometimes you hav to keep in 1st at lights. ### could be the problem the car is completely stock?

 

[crusher966]

Check your vaccum lines.

 

[wkmitsu]

Do you have a CEL?

 

[xander061]

no cel, and now it wont start without using my jump box which mean the alternator is bad but could that cause an idle problem too? goin to take the alternator to get tested 2moro

 

[wkmitsu]

Check all your intercooler piping and vacuum lines. It could also be a problem with the idle surge controller or the throttle position sensor possibly. As for the alternator problem, it just might be a coincidence that went bad at the same time.

 

[inix92]

I had the same problem with mine but mine was a bit worse if i didnt tap on the gas at a light it would stall on me, what you want to do is switch 2 things and go in this order. Its most likely your ISC or your entire throttle body (can get it the entire thing at a junk for like $50) or check your fuel pressure and make sure your getting enough if not switch the fuel pump.