So I've got a 12 Cruze that I am at my wits end with this issue. The car is stock except for a modded stock airbox and a tune. What's happening is right around anywhere 100-300 rpms before the set shift point the car is cutting fuel bad, leans out 100-300 rpms before the shift, during the shift and even seems to continue on maybe a little after the shift. Not sure how long it would continue to lean out because as soon as it does and I see knock and unfortunately hear the motor pingingI let out of the throttle of course!
Logging anything and everything that would tell me what could be happening hasn't told me much of anything unless maybe I am some sort of moron! Lol. My commanded power enrichment does not change during this leaning out, fuel pressure does not drop what so ever during this lean out period. I am logging "fuel cut type" which says "none" during this leaning out. I have done everything I can think of to the tune and cannot get this issue to go away.You name it I've tried it! Have raised my rev limit way up, completely removed upshift torque management etc etc etc.... Now I have been tuning for several years and I am not stating that I am some tuning God by any means BUT I have never come across a problem that's got me stumped like this one. No codes of any kind being set by the PCM. This fuel lean out always happens starting right before the set shift point. As a test I lowered my shift points by 400-500 rpms and bam still had this fuel cut again starting 100-300 rpms before the set shift point. Stock tune or a tune making less power doesn't do this. I can post my tune later when I am on a different computer. Don't currently have a log because laptop decided to take a dump the other day so I lost a bunch of logs etc... Great timing as usual for that to happen.
Just have this screenshot which obviously just shows it leaning out by what the o2 mv readings are doing and yes I have verified it with a wideband hooked up as well.
Any thoughts anyone? I'm stumped.
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