My a/f is fine WOT and PT but just cruising around but sometimes the a/f pegs out lean 17/1 at steady throttle in tc lock. If I blip the throttle it will return to normal but soon go way lean again. After a while it'll run 13's rich and then stoich again. All this at steady cruising throttle. All this started the day after the 4L80E swap. The only thing that changed other then the wiring was the drivers side exhaust had to be re-routed do to the deep pan on the 4L80E. Having the truck dyno tuned next weekend. Hopefully they will have some answers.

 

lol, mine used to do the same thing...started right after I did long tubes, damn that AFR gauge would bug me. I learned to ignore it. It doesn't seem to do it anymore, since I went MAFless.

 

Did you ever figure this one out? I am having the same problem...

 

can u post up a scanner log?

 

Yea, I'll do it tonight or tomorrow morning. It always does it in the morning.

 

How old are you factory O2 sensors? I would bet if you logged them one or both are being lazy...

 

First get that wideband hooked up to your scanner and do some Ve tuning with % AFR error (not by trims). Looking at your Ve LTFT histo, it appears a little off. I would then do the same for your MAF (using your wideband).

Did you by any chance have the A/C or the defroster on during these scans?

 

I did have the A/C on. Is that was the timing dips are? I didn't think about that one.

I'll see if I can wire that wide band into my interface. I don't have the EIO version of HPTuners.

 

More than likely.

Using the wideband is pretty much the only way you are going to safely tune the upper end of your Ve and MAF (provided you are not SD). A steady state dyno tuning session wil make short work of it for sure. Keep us posted.