Checked everything for vac leaks that I could think of again, and nothing to be noted. I replaced the MAF today with a brand new OEM unit and it seemed to run smoother,

I was able to hook up VCDS (VW/Audi diagnostic software) and pull data logs from about a 5 mile drive around town. I logged short term fuel trim for bank 1 (the side that appears to be functioning properly) and bank 2 (problem side). From what I see, the O2 sensor reads mostly correct for a period of time, and then it basically flatlines at 1.0 lambda with small variations around it. This means its keeping 14.7:1, but during WOT it should be reading <1.0. The 2.0 spikes are from liftoff when the injectors are basically shut off. Bank 1 registers these spikes, but bank 2 keeps it at 1.0.

What would cause the O2 to be functioning properly for a short amount of time (roughly 3 mins, car was already up to temp), then practically go comatose? I am not fully convinced that the o2 is the culprit here, since its already been replaced 3x. I did get a P0153 pending code for low refresh/update below threshold.

Charted on a graph, Blue is bank 1, red is bank 2.

Attached Thumbnails

 

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth