Have a 01 TA Ws6 a4, has mild cam full exhaust and converter. Nothing too major. I have had the car dyno tuned. The trouble that im having is the o2 sensor on the driver side, bank 1 sensor 1 is not responding. The passanger side is working just fine and I have the back 2 sensors deleted. I have changed the sensor multiple times, gotten new extensions, and even went back to the shop that i had it tuned at to look at it again. I have latley re-run new 02 wires from the pcm to the sensor and that is not fixing the problem either. Is there some way that the tune is messed up?? Only reason that i ask this is because this sensor that is not working is reading the same mv as the 2 that are deleted approx 447-450. Please help, i just dont know what to do anymore.