2G Running rough

[Infamous2021]

So I just bought a gsx and had a friend set the timing because it was off, but my car is running better then before, but now is idling high. I've checked everything and adjusted the idle screw but still dies out on it's own. I haven't done a compression test because I'm not sure how to do that, any help would be awesome.

 

[CanadianTalonTC]

Welcome to the world of DSM's.

There are several factors in play for idle and it changes throughout the warmup cycle.

To start, ensure you have 0 boost leaks (check TB shaft seals, BISS O-ring etc especially).

Following the factory service manual procedure, ensure your throttle stop and TPS have been adjusted correctly.

Lastly, you'll need to follow the directions for setting the BISS.

Do you have any logging software like DSMLink? That will change my next advice.

 

[XiKeiyaZI]

Last post is entirely accurate, but stepping in 2 days late to add -

The idle of these cars can be very touchy. If the throttle plate + BISS screw + TPS aren't adjusted juuuuust right they'll get a bit fussy and give you high idle or idle surging. They all rely on each other to be correct. Assuming that there are no outstanding vacuum leaks, there's a pretty systematic process you go through to get everything set right. Granted my experience has been with 1G's or 2G's with 6 bolt swaps, adjusting the TPS, BISS, and throttle plate has always come down to a touch and go situation without using ECMlink or anything to adjust it easier.

There's a few write ups floating around to check on. But the basic service manual should explain exactly how to do it. Granted the ISC is working properly and the seal there isn't leaking and causing an issue.

This mayhaps help