[RESOLVED] WBO2 Lean, SAFC Corrections Rich

[spyderturbo007]

Well, I stumped and need a little help.

I finished installing the AEM UEGO WBO2 today and went out to make sure everything was working properly. Made a 2nd gear pull and found that my AFR looked to be about 11:1 or there abouts. It was hard to look at the road and the AFR gauge.

Drove around a little bit and decided to make another pull in 3rd gear and now the WBO2 is showing me an AFR around 12.5:1. I did hook up the analog output to the ECU's rear O2 sensor input, but my freakin' logger batteries went dead before I was even able to get a log.

The thing that is getting me, is my SAFC correction factors are all indicating that I'm running rich. They are about -30% which pretty much the correction for a 9.5:1 factory AFR. I'm not sure what's going on here because if I had a boost leak, I would see inflated rich AFR's as opposed to a lean AFR. The only thing I can think of would be an exhaust leak before the WBO2.

Why would there be such a difference between 2nd gear AFR's and 3rd gear AFR's? We replaced all the exhaust gaskets when we pulled the DP to install the bung so I really don't see there being a leak.

Keep in mind, I'm running a 50/50 mix of MeOH and H2O through a 6 g/h nozzle. Also, I have read that people say their throttle body is normally cold after installing MeOH injection, but mine is not. I'm sure the MeOH is kicking on because the LED lights and I've had to fill the tank once already.

Any thoughts?

 

[CanadianTSi]

Check for any fuel delivery issues, make sure you didn't blow the line off the FPR or anything like that.

 

[spyderturbo007]

That's a good thought and something I was worried about when I tapped for the MeOH injection. I have two lines tapped into the FPR line, one for the boost gauge and one for the MeOH injection. I couldn't find anything about tapping multiple lines off the FPR, so I figured it wouldn't be a problem. Could that be causing the problem?

EDIT-> I guess one way to check and make sure there aren't any leaks in that part of the system would be to pull the line off the FPR and hook up my compressor? That wouldn't hurt the solenoid on the end of the line would it? That way I could be sure there isn't a leak that's bleeding pressure under boost.

 

[CanadianTSi]

No it won't hurt the FPR.

 

[spyderturbo007]

Well, I checked the FPR and all the lines are good. Pulled off the line to the FPR and pressurized that part of the system to 20psi according to the boost gauge. No leaks from either the boost gauge or the line to the MeOH injection. It looks like everything is good there, unless the FPR is causing the problem.

I also performed a smoke test on the exhaust and found that there is a broken manifold stud leaking exhaust and the flex section is also leaking. I'm guessing that's my problem, but I'm not sure if a leak at the flex section would cause things to read that lean on the WBO2.

Went ahead and ordered a stud kit for the manifold, ported 2g manifold since mine looks like it's developing a crack, ported O2 housing and a new flex section. Hopefully I can get this taken care of next week after I get the parts. I'm hoping I can get the manifold and O2 sensor housing installed without having to remove the turbo.

 

[spyderturbo007]

I'm just going back through some of my old threads and marking them "Resolved".

The problem turned out to be a leaking flex section. Replaced that and everything is fine.

 

[pneumo]

Thanks for the update. It's nice having more answers to those mystery problems.