With all this oxygen sensor talk I think about a radio mechanic who said someone came in and was told it would cost so and os to diagnose problem with his car. He didn't want to spend that money.
Instead that weekend he got the Budweiser diagnosis and they replaced two oxygen sensors. It ran worse than before. So the car ended up at the local shop anyhow. Mechanic found both oxygen sensors were off and neither was needed. They put the originals back in and then did diagnosis.
Guy ended up spending a whole lot more because of wrong diagnosis and aftermarket oxygen sensors. If you're gonna try the oxygen sensor, get GM.
Dual auto air on both