I agree with swapping in a new O2 sensor before doing further troubleshooting. All brands have had issues with errant codes, due to the way sampling and key-on tests are performed on OBD2 cars.


As a for instance, a couple years of Ford F150's had a "glitch" in their testing sequence - if the computer was at a certain spot testing the air bag system - testing the front sensor and speed sensor - and you slammed the passenger door, it would see speed and both sensors tripped and blow the air bags.