Short term fuel trims max out, car keeps going lean randomly. Chrome ECU tune attchd.

[vr4whore]

Car runs/drives perfect at WOT, but when I feather the gas while coasting I feel bucking. and hesitation, sometimes while driving my AF would jump to 16-20, it will NOT stall, then it would fix itself and I would continue driving. Sometimes while sitting at a red light it will also go super lean 16-22 and the car will NOT stall.

Looking at the logs we figured the short term fuel trims would keep adjusting and eventually max out at 12. I attached my main tune if someone can take a look at it.

I have tried the following:

New factory o2 sensor, no help
New wideband sensor hooked up as a narrowband to the ECU, no change.