2K Engine Idle PROBLEM

[SonomaGTlover]

I've been trying to track down an issue I have with the SY. It starts and revs fine and i was going to begin tuning on it but for some reason it won't idle down below 2000. Thanks to JSM we've pretty much ruled out the ECM and thought it might be a vacuum leak somewhere. I've searched high and low and feel confident that I don't have any unplugged lines anywhere. The pic below shows where everything leads to. The EGR has been deleted and the heater controls bypassed for now so my vacuum lines are quite simple.

Has anyone else ever expeienced anything like this? I found THIS THREAD but it didn't help much since my issue is constant and not temporary.

 

[myclone]

Re: 2K Engine Idle PROBLEM

Brake pedal stiff? Could have a busted diaphram in the brake booster causing a vac leak (just a guess). Id pull the hose and plug the port for it in the manifold just to rule it out.

 

[SY2455]

Re: 2K Engine Idle PROBLEM

Brake pedal stiff? Could have a busted diaphram in the brake booster causing a vac leak (just a guess). Id pull the hose and plug the port for it in the manifold just to rule it out.

What he said. After you check out the things I pm you about, you may check the TPS to find out if it's going bad.

 

[Don W.]

Re: 2K Engine Idle PROBLEM

Another thought might be the TPS. It needs to show less than 1.0 volt at idle using Datamaster or whatever if you have it. Voltage is linerar (sp?) from there to WOT voltage of about 4.5.

Any codes?

 

[QUICK STORM]

Re: 2K Engine Idle PROBLEM

i assume your timing is at 0*, did you knock any HVAC lines loose, this is definately a vacuum leak. try the bike tube test.

 

[SonomaGTlover]

Re: 2K Engine Idle PROBLEM

Ding Ding Ding... We have a winner! :tup:

I was prayin and hopin that it wasn't the brake booster eventhough I have an issue with it.
Anyhoo... I took the TPS out by hand so I was very happy to see that. When I got it out it
seemed normal so I sprayed it off with electriconics cleaner and shoved it back in there.
Got the channel locks on it and gave it a final twist and Bingo, idles down nicely.

Thanks guys.... Now I can finally get down to tuning.

 

[QUICK STORM]

Re: 2K Engine Idle PROBLEM

glad to hear you figured it out, sorry i couldn't have been any help

 

[Don W.]

Re: 2K Engine Idle PROBLEM

Thanx for letting us know. So often no one does that and we're left wondering...

 

[SonomaGTlover]

Re: 2K Engine Idle PROBLEM

glad to hear you figured it out, sorry i couldn't have been any help

Eventhough you didn't have the solution it was pleasing to see the posts of a variety of things to check. Funny thing is that I had the TPS break on my GT and had the same problem. This one didn't break so the symptoms were a little different leading up to it. It just never dawned on me that I had the same problem. It's hard to think of everything sometimes and that's why I am so thankful to have this board.
Aren't we about due for another round of donations?
By the way... What is the bicycle tube test?
Search just revealed suggestions to try it but not HOW to do it. I'll have to search again.

 

[Jimmy]

Re: 2K Engine Idle PROBLEM

Find vacuum leaks