Hey everyone,
I don't post often, I usually just lurk and learn. However, this time I'm stumped and so is my tuner. I tried searching far and wide for something close to an answer and found nothing. So here goes.
1999 Cobra that has a terminator swap. ZMR3 PCM. At idle the Bank 2 (driver side) O2 sensor reads correctly however, at part throttle operation the car thinks it is getting too rich and starts pulling fuel. The voltage spikes to 1.5v on the O2 sensor and will not drop back to normal. The wideband shows the car getting more and more lean as the PCM attempts to correct for the "overrich" condition and it never corrects. I have tried 3 different O2 sensors from 3 different brands, all of which were new. I tried swapping O2 sensors from side to side to see if the problem followed. It does not. It stays on bank 2. Full throttle operation (open loop) and idle operation work fine. Part throttle (where the car is 99% of the time) is where the issue is. In order to drive the car at all my tuner gave me an open loop tune until I fix this issue. He gave me the closed to tune to store as well so I don't have to bring it back once it is fixed.
My tuner suspects it has something to do with either the signal or signal return wire. The heater wire gets 12v all the way through the whole wire routing. I was curious if anyone has experienced anything like this or has any suggestion on where to go from here?
As of right now I have cleaned the O2 plug contacts and ensured they are seating well. I can't check for continuity just yet, I have to go get longer test leads for my multimeter. I am open to suggestions and will check as time allows.
I hope this is in the correct place to ask this question.
I don't post often, I usually just lurk and learn. However, this time I'm stumped and so is my tuner. I tried searching far and wide for something close to an answer and found nothing. So here goes.
1999 Cobra that has a terminator swap. ZMR3 PCM. At idle the Bank 2 (driver side) O2 sensor reads correctly however, at part throttle operation the car thinks it is getting too rich and starts pulling fuel. The voltage spikes to 1.5v on the O2 sensor and will not drop back to normal. The wideband shows the car getting more and more lean as the PCM attempts to correct for the "overrich" condition and it never corrects. I have tried 3 different O2 sensors from 3 different brands, all of which were new. I tried swapping O2 sensors from side to side to see if the problem followed. It does not. It stays on bank 2. Full throttle operation (open loop) and idle operation work fine. Part throttle (where the car is 99% of the time) is where the issue is. In order to drive the car at all my tuner gave me an open loop tune until I fix this issue. He gave me the closed to tune to store as well so I don't have to bring it back once it is fixed.
My tuner suspects it has something to do with either the signal or signal return wire. The heater wire gets 12v all the way through the whole wire routing. I was curious if anyone has experienced anything like this or has any suggestion on where to go from here?
As of right now I have cleaned the O2 plug contacts and ensured they are seating well. I can't check for continuity just yet, I have to go get longer test leads for my multimeter. I am open to suggestions and will check as time allows.
I hope this is in the correct place to ask this question.
