Serious stft issue
 

So last July I installed my cx racing fmic, matt damond occ, test pipe and some other non engine related mods and starting that night I got the notorious smoking turbo. But that's not the point of this post. My problem started about 3-4 months ago when I got a CEL. I popped my V3 in and I get the too rich at idle code and my stft's after idling for a while max out at -25 whatever. So I talk to my tuner and local vegas group and we first and foremost thought boost leak. Went to one of the guys house, did the test, and found one MINOR leak. Tightened it up but it didn't affect the trims. Next I was told to check injectors and the occ. I pulled my plugs which I had just put in about 5-10k miles ago and none of them were fouled up, nor did I see any wetness in any cylinder with KOEF looking for signes of a leaking injector. Next I bypassed the OCC and just hooked the 2 hoses together and let it idle for a few minutes. And it appeared my trims were a lot better. After a few minutes of idle, the lowest it would go was about -6. So my thought was ok, the occ has something going on with it. Gave it a look over and discovered the bottom drain piece wasn't tightened all the way to the can. So I took it all the way off, put some thread seal tape and screwed it back on and tightened that bitch up. Re-installed the hoses and started it up again. Again it didn't go below -6 after 3-4 minutes of idle. So I thought ok, problem solved. Left my buddies house and drove it home. On the way home, I hit a red light and was sitting there for a few minutes. Kept an eye on my V3 and there it was, dropping stft's like crazy back to -25. So now I'm beyond frustrated. What is going on with this god damn thing? Anyone have any ideas on what to check next??? I'm losing my mind, and money with my horrid gas mileage.

bump for interest

Post some logs or tell us if anything else is amiss

Sounds like a boost leak still, but could be a sensor going out, bad connection, etc

Honestly, nothing else really seems to be wrong aside the smoking turbo but I'm replacing it with an S3 when BNR has one to sell.... I was told to check for an exhaust leak, so I'll check that out next. I did a good boost leak test with a soapy fluid on all the FMIC piping and we fixed any small leaks we found. Something is just very wrong and it's probably going to be something stupid. But god damn im frustrated

i had these symptoms with purge valve.

faulty purge valve will sometimes throw its on code but not always.

boost leak test and evertyhing is right and tight, but will still get that abnormal STFT.

Thanks for the recommendation. Did you flat out replace it or did you try to clean it first? I looked and saw it's a pretty cheap part so I'm thinking I might just not mess around and replace it unless there's a simple way to just clean it or something.

Purge valve.

The rock auto one is something like 15$

Some people have apparent success with cleaning it, just re-lubing it. But that's never worked for me, so I've always replaced it.

New purge valve, same problem. It just seems like an injector issue because in cruise control going like 70 on a flat freeway my stft's are between +/- 4ish until idle, then it plummets to -25

After you installed the purge valve, did you re-flash the ap?

Personal superstition, I sometimes completely uninstall the AP and reinstall to find my fuel trim issue has somehow resolved, when simple flashing did nothing.

A boost leak (leak post turbo) wouldn't cause negative fuel trims at idle.

At idle the intake tract is under vacuum, not pressure, so if there is a leak, it would be drawing in un-metered air and causing positive fuel trims.

As the others have suggested, it sounds like a PV issue. Might want to check/clean your air filter and MAF sensor also.

Well I installed a brand new PV, I have cleaned the air filter recently, and a guy I talked to tested the MAP and saw it was getting proper readings. But I will check the filter again.

What kind of tune/map are you running?

Has the MAF been calibrated to your setup?

I'm running a tune I got from my tuner. It's after MAF cal but I never did the WOT portion because it was a waste of time to hone it in since I was replacing the turbo, which I am as soon as BNR makes one for me to buy. I use the tuner Marco Vega-Colon. Not sure if you know of him but he does nearly all the tunes for all us Vegas guys. I've been talking to him a lot to also find the issue. He wants me to check for an exhaust leak next.

I just find it odd the OCC hasn't caught anything since I've installed last July. I have a thermal gasket to install next Saturday and I'll replace the pcv just to be sure that's not clogged or something.

oh the joys of figuring out stft issues. i had some months ago and went through the entire play book just to find out the damn occ wasn't closed all the way.

I removed the occ completely and bypassed it to idle, but I didn't drive then idle to really test it. I might do that next also. It is fully closed though.

uninstalled and reinstalled AP to no avail.

http://www.lignumgroup.com/yahoo_sit...113336_std.jpg


http://thumbs.dreamstime.com/x/stacked-logs-2965530.jpg



https://familysearch.org/learn/wiki/...earch_Logs.jpg

ill upload a lof of 40 sec's of idling.

40 sec ish log after warm temps of driving.

Exhaust leak? You need to post more variables in your logs. Search for logging parameters

That log is useless.

As stated above, you need to log more parameters.

Just log everything.

Datalog 1 is idling for a while after driving.
Datalog 2 is some around town driving for a few minutes with idles at stop lights and such while warm.

Was anyone able to peep the logs and maybe see something?