Funky 02 readings

[SpoolinUpGN]

The other day, started the car and the scanmaster turned on as usual and i noticed something odd: 02's read: 000. Stayed like that for a bit, then went 005 007 009. I shut it off. Starting it again had a similar result, then i decided to let it sit. All other functions on the scanmaster seemed to read as usual. Started it later and it seemed to go back to normal.

It happened again today, and when i put it in gear it stalled out. Let it sit, maybe 10 or 15 min, started it up again, and 02's were reading away on scanmaster. Unfortuantely, I don't have crosscounts since my SM is a 2.0 not 2.1, but, should i assume that my 02 sensor is bad? When started back up, 02's were pretty unchanging, staying on .394/.396 until it warmed up and exited closed loop or open loop whatever the blinking decimal point means, then they seemed to go back to normal. Anybody ever seen this, i couldn't find anything about "zeroing 02's" with the search feature.

TIA as always guys

 

[2QUIK6]

Was this with the motor at operating temp and closed loop?
If so, yes, the O2 may have crapped out. Get another one and see what happens. Get an AC Delco sensor, I've never had a Bosch sensor last much more than a few thousand miles before they get lazy compared to a Delco ones even with unleaded gas.
If its not the O2, then at least you will have a spare.