Air/Fuel Readings

[Sibola]

Good day, need some help. 2008 apex stage 2 mpi s/c running 10psi with head shim. Just installed BOV and RB3 and EXCELL mountian lite tunnel dump exhaust. Sled started up fine, idleed like a kitten through it's warm up stage A/F was 12.8. It idled down to 1500rpm then the A/F starting jumping all over, 12.8 up to 16. Still idling fine but A/F all over the place. Rev sled up to 2500 rpm, A/F sit steady at 12.8, hold it there for a minute. Then it would slowly rev up bye itself to 3500 rpm, then A/F start jumping all over the place again. Let go of throtle, the revs drop down to 950-1000. Still idling but not that great, A/F all over the place still. This went on for about 5 minutes, notice smoke coming up through engine compartment. Pull side panel off look in threw chaincase can hear a exhaust leak. Shut her down, take fuel tank off and sure has chit right side flex pipe from block to header is broke. You think this exhaust leak could cause all though's above mentioned problems. Sure hope so or . Well got lucky phoned my dealer and has 4 steal ones in stock, so much for titatium be stronger. Go to town tomorrow pick them up and install, cross my fingers legs and whatever else that this resolves the issue. But something tells me not going to be that easy.

 

[racinstation]

An exhaust leak could and will cause this problem. Also, what brand of AF gauge are you using? I have had very poor luck with the Innovate stuff and it never seems to work right. AEM is awesome.

 

[Sibola]

Thanks, sure hope your right. Allready feel better. It is a Autometer wideband.

 

[mtdream]

I would check your throttle bodies and your intercooler hoses...I had mine come off and result was the exact same...

 

[kinger]

Yes if it sucks in fresh air through the broken exhaust and then goes to your AF gauge it will be all over the place. Like mtdream said could also be a leak on the intake side.

 

[wienerwater]

Might want to read my previous post about a "Ticking sound" a few threads below.
Had mine out today after repairs, and AF is more steady and realistic. I need another ride to get the AF readings on higher boost throttle when climbing. Today was a bit testy with bad light and just watching where we were going.
I think any noticable exhaust leak on the exhaust side will throw it all out of whack for sure, a vacuum effect going on.

 

[Sibola]

Found the exhaust leak, and fixed it today. Sled idle's perfect, A/F reading's steady. Not jumping all over the place like before.

Now it's time to start dialing in the RB3.

 

[gsxr]

great