Past Saga of low voltage to O2 sensor

[GPFred]

For those who are familiar with the O2 saga I had with my 2000 GP, well, I think its been fixed. After spending multitudes at the dealer in having the intakes done, new cats, new O2 sensors, new MAF, new PCM, and a fuel injector job by me, the O2 problem may be done. A few weeks ago when I changed the filters and oil, I also replaced the fuel filter. A week later the SES light went out. I took the car to Chicago on a trip and not once did I experience any bogging down upon heavy acceleration, in fact I got on average 33 MPG with A/C and averaging 80mph. Its getting 22-24 mpg around town. The car is running great. I have been pushing it to see if it will set a code again, but no dice. I know that when I first bought the car I did a complete tune-up and I believe I changed the fuel filter. If it had been the fuel filter all along, I'm surprised that Pontiac doesn't have something to refer to when this situation occurs. I don't recall what the code was that got set, but it was low voltage at the O2 sensor bank 1 sensor 1. Sheesh!! This is definitely one for the books. Thanks for the help and suggestions on this problem.

[BNaylor]

Thanks for the feedback GPFred. I recall it was a weird one. Didn't you have subsequent DTCs that showed a fuel trim problem. Just cross your fingers and good luck.