Idle wont catch

[2g4G63]

I have a 98 GST. Ever since i have owned the car, it has had this idle problem. Lets say im cruisin around, and i get up around 3,000 RPMS or higher, then either pop it in neutral, or hold in the clutch, the idle drops down to about 0 rpm and sometimes jumps back up to normal rpms or occasionally it has stalled on me. This has happened while i have been coming to a stop, and just reving up the engine, the idle just doesnt want to catch itself for some reason after it gets over 3 grand. I have found myself when rolling to stop and instead of putting it in neutral, i have to wait for the rpm's to drop below at least 2grand then put it in neutral. at a stand still, the car idles fine, but sometimes drops down after a little while and shakes the whole car, this is related to the idle not catching itself. ANY IDEAS AT ALL? thanks

 

[lenhof13]

is your bov vented if so i know 1g's will want to stall

 

[steve]

What is your normal idle speed?
Check your IPS (inside the TPS on a 2G) that tells the ECU the throttle is closed.
Check the ISC and make sure the coils are good.

Steve

 

[c4uldr0n]

might have a vacuum leak... BLT (boost leak test) ftw

 

[steve]

I don't know how I got suckered into replying to a thread where the OP's question is about 3 years old. I should hope he has solved the problem by now.

Len, thanks for bringing this one back from the dead.

Steve

 

[99gst_racer]

You were HAD, Steve.


Closed.