CEL (O2 Sensor) Intermittent

[NY94J30]

While I've been waiting for 4 new back ordered O2 sensors a few weeks, I've noticed that the CEL has gone off a couple times, and stayed off for some time (100-200 miles) each time.

My question is this, when the CEL is off, is the car running properly, or still running rich to some lesser degree?

[elwesso]

Is the code for the front or rear o2 sensors? The fronts are the only ones that have mixture control, the other ones are there to be sure that the cats are doing their job.

[NY94J30]

It's a rear sensor. Code 0141. Interesting that it doesn't affect A/F. My gas mileage has suffered significantly since the CEL came on. I'm getting ~15mpg on full hwy trips, when I was getting ~21 prior.

If I'm not getting any other codes for O2 sensors, are the other functioning correctly? i.e. is it an all or nothing proposition, or will resistance ranges affect their function?

Alternatively, I assume it's a knock sensor issue.

[maxnix]

O2 sensors are good to replace in pair so the duty cycle is matched.

Is it Joe or the NTK that are out of stock?

[NY94J30]

It was NTK. I have them coming in this week. I ordered the 4.