Nissan Repair: oxy sensors, nisson, hi john

Question
1997 Nisson Quest, 145,000 miles: PO135  check light. Oxy sensors problem. Changed both sensors, erase light and it came back on. What next?

Answer
Hi John -

Perhaps it is not the sensors, and the vehicle is running a little rich or lean. To check this you would have to put it on a diagnostic tester and check the emissions level.

Is there any code besides the O2 sensor?

Thanks
aloha
calvin