basics: I have a 2009 e67 running ls2 setup similar to a ctsv or tbss. Bank 2 o2 readings are good. Bank one stays between 430 and 460. Even if I unplug it. I checked wiring all the way back to the pcm. Installed new o2 and even swapped o2 from pass side with no change. It reads the same voltage via meter not running as the other side. It does develop misfires once in closed loop due to fueling from o2. No vac leak, no exhaust leak. seeing as how it does not change when unplugged I was thinking it possibly could be the PCM. looks like if it was a wiring issue it would show on meter. It does ohm from o2 to the pins on pcm. This one has about stumped me. The only thing I haven't tried yet is to make a o2 extension harness and plug left side into right side harness. anyone ever run into this before?