OBDII O2 Sensor Not Ready

[oldskewel]

With my issue, I never did any attempt at a specific drive cycle. Closest I got to that was to suggest my kids (who drive the car) take the freeway vs. surface streets if they have a choice.

Almost certainly, that full drive cycle was not ever done in a single drive.

Regarding CA allowing one monitor incomplete. I don't know definitively, but I have read that the EVAP monitor can be incomplete, but no others. I would not rely on that being true unless finding a good source, though.

Looking through my notes of what completed and when, everything except O2 sensor heater would be complete within about 30 miles of normal driving. A couple of times secondary air and EVAP would take a few extra miles beyond that. And then the O2 heater took over 200 miles.

So since you have O2 (non-heater) incomplete, it would make me suspect an actual issue with the O2 sensors. The sensors are pretty cheap - around ~$50+ for Bosch (OES) for my 2001 3.0i. At some point I decided it was worth it to just replace the downstream ones (had replaced upstream ones early in my ownership) rather than continue the research project with that as a possibility. But I did the work myself, which is a factor in cost and convenience.

BTW, the biggest lesson I learned from my issues was to get on the smog check ASAP (i.e., as soon as the registration renewal arrives in the mail, vs. waiting for the deadline to approach). Having a time deadline waiting for things to reset or codes to appear sure made everything tougher.