bringing this back up. How'd yours turn out? we've been having a really bad time with this truck. in OL, we tuned the VVE and got damn near perfect fueling. then we tuned MAF only OL and got damn near perfect fueling. Added them together and it was wayyyyy offf ... played with the MAF until we got it close, again in OL ... then turned on STFT and put it in CL and it was completely off again! Still my buddy was able to get it close enough ... but then after a few days and the weather changed, it all went to hell again! I'm tired of this damn thing. Almost wanna rip it all apart and go N/A.

 

Just run it OL. It's a freaking turbo setup.

BTW, if you haven't noticed, turbo setups can be very temperamental.

The 02 sensors may not be functioning properly if they're located pre turbine

 

It's got a decent tune on it right now. I still need to go back and do some more after I get a 2 bar map. If I roll into the throttle, and stay somewhere around half throttle I get a decent lean spike. If I go wot the lean spike is on about 1/2 a point afr.

Have you thought about going speed density?

 

As for the O2 sensors, they seem to be working .. well that's relative cos I can't compare them to any other logs.

The driver side is just off of the manifold (in stock location) but the passenger side that also used to be in the stock location was now moved to downpipe and now seems to read much better than before as it used to be very close to the merge between the two banks and also the wastegate. The trims for both sides are now within a few points or the same but used to be about 10 off before consistent.

 

My goal was to be able to run the maf and it seems to work in OL ... I may be fighting a losing battle to try and combine with VVE and CL

 

It works! MAF and all, it works! 15psi safe tune and more possible with ethanol

 

So how did you fix it??