O2 Sensor Replaced but Code PO154 keeps coming on.
Asked by TahoeRay Jun 19, 2018 at 07:48 PM about the 2000 Chevrolet Tahoe LS RWD
Question type: Maintenance & Repair
A month a ago my check engine light came on. Code reader says PO154 (Bank 2 Sensor 1). So far I've replaced, O2 sensor 3 times, a Mass Air Flow sensor, the Throttle position sensors twice, and Plug wires. I've taken it in to mechanic shops, one can't find a problem, he checked for vacuum leaks, checked EGR valve, and cleaned the throttle body. An electrical shop told me it could not be anything except a bad pigtail on the 02 sensor or catalytic converter... others say not because the sensor is upstream and the plug is good. Any ideas on the problem? Thanks
5 Answers
This could be a vacuum leak, exhaust leak or a wiring problem.
While we will keep looking, mechanic spent over an hour looking for exhaust and vacuum leaks, nothing found. He ruled out a wiring issue because his Code reader says, the O2 sensor is working normally just like the other O2 sensors when looking at live data. Thanks
Was the reading done after clearing codes and going for a test drive until code came back?
Was this ever resolved? I'm having the same issues on a 2004 Tahoe 5.3. I believe I have a short in the pink wires from the PCM. This is a guess right now but they won't buzz out correctly to their pins, but both buzz to pin one C1 Blue PCM connector which is ground. I'm rying to determine if this as big of a problem as I believe or if I'm not thinking correctly. I'm not close to an expert at finding electrical shorts, I'm using basic wire troubleshooting. Again if you resolved it what was it? Thanks in advance!
