I have a 2002

 

Ran some Chevron Techron and Shell V-Power and went for a spirited drive...and it looks to be good. Fingers crossed, but maybe this is all i needed.

 

Ok so it's still doing this bogging at idle and it's driving me nuts. Definitely getting worse and more often. Upgraded to an '02 ECU, ran chevron techron and seafoam through my gas. Nothing. Decent chance it's an oxygen sensor? I'm so lost here.

 

UPDATE: Did a quick seafoam TB treatment last night and when I took off the intake to do it, two of the vacuum hoses popped loose that I didnt see. That forced a code to be thrown (P0411) which when I checked it, also showed a pending code. So basically what I am gathering from all of this is the initial problem was a vacuum leak. So basically there is a problem in my air system somewhere I need to find.

 

honestly, i reoplaced my entire throttle body and all my idle issues went away. a good cleaning of the TB, and IAC will drastically help as well

 

K so after examining everything i really dont think its vacuum. The only reason it threw that code in the first place is because i didnt hook up those vacuum lines. I reattached, cleared the code, and no more code. TB might be next.

 

Check the tps sensor. I think it is related to this. I forgot to add earlier in the thread that I have an aftermarket thottle body, so my idle adjustment screw is a little different. I did check the factory throttle body and it does have an idle adjustment screw. You should adjust this to have the idle a little higher, it solved my issues.

 

Will definitely test the TPS next. I cant find that adjustment you are talking about on the stock TB. I'll have a look in the manual tomorrow but if anyone has pictures to help out lmk. If I find out I'll also post here. Just really sucks not being able to enjoy my S because of these issues. I appreciate all the help from everyone though.

 

Ok, here is where I believe the idle adjustment is on the factory throttle body.


This picture is looking at the front of the throttle body as it is mounted on the car.




This picture is looking at the back side of the throttle body upside down




If you loosen the nut the set screw should turn upward to increase the idle speed. Then tighten the nut when you have the desired idle with minimal bog. My throttle body is different and was easier to access. The set screw may be an allen head on the end so you may need to adjust up with an allen wrench then retighten the jam nut.

 

Thanks a lot man. My idle looks to be around 900-1k rpm and i dont want to set it any higher then that. Something is definitely wrong/broken. I think its the TPS and ill probably test it tomorrow after work. I'll keep this in mind though.