Code 172 and 176 Bad O2 Sensor?

Still Crusin

Registered User
Check engine light came on and stayed on for about last 10 miles while out running errands. Conducted KOEO and KOER tests(car was still warm). Codes 172 and 176 were read during KOEO test. Code chart states this is "Lack of Oxygen Sensor (HEGO) switches, indicates lean (RIGHT SIDE)

Code 176 is same except for LEFT SIDE.

After both KOEO and KOER tests were conducted, I started engine again and let idle for a few minutes and CHECK ENG light did not come on again.

I've never changed any O2 sensors on this car. Think this is culprit or something else? First time I've ever had this code.

Car is stock

I did a search on this question and found very little.
 
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when i got 176 i replaced my 02 sensors (went ahead and replaced them both while i was there) and never had that light for that code again. i got bosch from advance auto for like 42 bucks a peice and working great so far and i actually noticed a slight increase in gas milage.
 
Thanks for the advice. I drove the car again later and no check engine light, but I'm thinking the sensors are probably overdue for replacement since they are the originals since car was new.
Plus, it'll be something new on this car that I haven't done before. Was it difficult replacing the sensors?
 
not at all, i forget the exact size wrench or i would tell you. all you have to do is unplug them, screw them out, make sure the new ones are good, screw those in and plug them back in. i did mine while they were out side the car but should be easy anyway. probably no more than a 45 minute job.
 
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