Help...My Sti WON'T IDLE

[cobbtunedsti]

First let me start by saying I have a LEMON!!! My sti has never gone more than 10,000 miles without issues!!! I love this car and that's probably part of the problem.. Any how.. Ran my car out of gas 2 weeks ago because my gas station ran out of e85. So I didn't have a choice.. I just put gas in it Saturday and it ran fine.. I raced a supercharged c-6 vette Sunday and stroked it. Just after that my car die and wouldn't idle.. It starts fine and but cut out when driving it back home. It threw a po171 system to lean bank 1. I tighten all hoses and IC piping.. I personally think it's a clogged fuel filter???? Or pump???

 

[IGOTASTi]

We need Holy in here to help us. He's the man for this job.

 

[cobbtunedsti]

Who?? Lol

 

[IGOTASTi]

HolyCrapItsFast is George on the forum. He is good with this stuff. Also your stickers where sent out also.

 

[cobbtunedsti]

E85 and 91... Yes

 

[STi FR3AK]

Does your idle wander or jump?

 

[icudruln]

Check the fuel lines off of the Fuel Pressure Regulator?

When I threw the same P0171, I ended up having a bad rear o2 sensor and a torn IC coupler off the throttle body.

 

[cobbtunedsti]

No it just fires up and dies... I can drive it but it's running lean.. (Engine light) I talked to Neil at Cobb.. He said it's IC piping or Vac line????? I checked these already???

 

[icudruln]

No it just fires up and dies... I can drive it but it's running lean.. (Engine light) I talked to Neil at Cobb.. He said it's IC piping or Vac line????? I checked these already???

All clamps are secure for the IC piping? Are you TMIC or FMIC?

One time, a vacuum line behind the intake manifold, to the left of the throttle body popped off, causing a jumpy ass idle.

Tip: Grab some brake clean, let the car idle, spray the brake clean around clamps, couplers, and piping on the intake side of the car (pre throttle body). If the idle jumps after a particular spot is sprayed, spray it again to double check it. If it does it again, you found your leak.

 

[cobbtunedsti]

FMIC.. IC piping is 100% tight.. I could have spit a coupler though??? I'll check the hose after work today!! I have to keep the RPM's above 2,000 or it will die.. So it's kind of hard to check for leaks

 

[HolyCrapItsFast]

No it just fires up and dies... I can drive it but it's running lean.. (Engine light) I talked to Neil at Cobb.. He said it's IC piping or Vac line????? I checked these already???

Almost nine times out of ten this sort of thing is because of a leak somewhere in the intake plenum. Typically when it leans out that means the leak is after the MAF sensor and before the turbo. Do you have a blow-through or a pull-through MAF housing? This makes a difference when trouble shooting for intake leaks

Other causes can be fuel delivery related and the only way you will know that is with a fuel pressure gauge. Though it is unlikely, it still could be a pump or injectors or something like that but it is just easier to rule out the intake system first.

All clamps are secure for the IC piping? Are you TMIC or FMIC?

One time, a vacuum line behind the intake manifold, to the left of the throttle body popped off, causing a jumpy ass idle.

Tip: Grab some brake clean, let the car idle, spray the brake clean around clamps, couplers, and piping on the intake side of the car (pre throttle body). If the idle jumps after a particular spot is sprayed, spray it again to double check it. If it does it again, you found your leak.

+1 for the spray. I have also used starter fluid. That works nicely as well.

 

[STi FR3AK]

Like this?

this turned out to be the PCV vacuum line pinched under the manifold after doing my tgv deletes. I found it by doing a vacuum leak test with this homemade tester and an air compressor. I took off the intake filter and connected this to it

I found where the PCV line was supposed to go cuz of all the cold air I could feel coming from a nipple under the throttle body I couldn't see. The blue nipple on the right.

 

[cobbtunedsti]

Nice.. Keep ideas coming!!!

 

[IGOTASTi]

Put the IGOTASTi stickers on, and it will be fixed, lol.

 

[cobbtunedsti]

I have tried the PVC thing in the past and it didn't work for me..

 

[STi FR3AK]

I'm just saying it was my problem but what I was getting at was how I found it....vacuum leak test. I blew 20psi through the system. Also found out my intake manifold / tgv's weren't tightened all the way as I heard a little hissing from there and got a couple turns out of the bolts and was good to go

 

[cobbtunedsti]

Nice..

 

[cobbtunedsti]

Under my hood.. I'll let you guys know

 

[cobbtunedsti]

Still looking.. All hoses seem connected.. I'm losted

 

[cobbtunedsti]

Holy Crap.. I barely got the car to idle barely.. But I had enough to run and check under the hood.. It was missing and poping pretty bad and I seen smoke coming from around the turbo.. (Early this morning I discovered a oil leak on the oil return line on the turbo)..this could be the smoke???? When I started the car it revs up pretty high around 4,000 rpm's... I must have done something right because it didn't even idle before????