Idle Problems

[colbyc]

OK ive got a 96' gs N/T i know i should go boost and im going to sometime next year........but while i have this car it should run fine .....ok heres the problem whenever i start my car it'll start right up but will just die if i dont give it gas then i have to ease off the gas to keep it running then it idles down to bout 100 or 200 rpms then idles back up, ive checked vacum leaks, throttle body, etc....What could it be thank ya

 

[andy4g63]

ISC would be my guess.

 

[nongthep]

check engine light?

 

[4ced4g63]

TPS could also cause this. If the computer doesnt know where the throttle is at it cant compensate with the ISC.

Good Luck.

 

[colbyc]

nu uh the check engine light aint on,
so what could i do bout this??

 

[SeMi380]

I had this problem on my gst. I had horrible compression. I would start by doing a cylinder leakdown test and a compression test.

 

[colbyc]

aight ill check that this weekend probably, ill let yall know whats up thanks everyone

 

[DarkSideGS]

I had a similar problem with my GS. Instead of my engine dying out, it would do the exact opposite. When I turned on my car, the engine's RPM would jump to about 3,500 and stay there until i drove it around a bit. I changed my TPS and IAC sensor. It didnt fix the problem but it calmed down the starting RPM's a bit. Try that, maybe you'll have better luck.

 

[BulletShiftTSi]

My car did that when I did my motor swap, but for me it was just the throttle position sensor not being tightly on 100%

Also check to make sure your throttle cable is not wicked loose.

 

[Jeff99GS]

Bad IAC (Idle Air Control) I had the same problem on my GS

 

[95'RS-T]

i have a problem kinda like that instead my rpms go up and then come down to about 900-1k
and then i give it gas and they go up to 35k and hold there for a while, it sounds like there's a vac leak but i did a smoke test and didn't see any leaks so im thinking it could be a TPS or the IAC im not sure. Any Opinions? i dont want to spend too much money if i don't have to.