i replaced O2 sensor 1 on the passenger side 2 months ago to turn off the SES light. Light stayed off for a couple weeks then came back on when i went to pass someone on the highway. Two days later the light went off by itself. Yesterday, light came back on while passing someone again. Got it checked at autozone and they say it reads low voltage on all 4 O2 sensors. Also, it seems to be harder to start now. Is it possible that all 4 sensors go out at the same time? even the one i just replaced? would that cause a starting issue? Please help. thanks

 

whats the specific code number?

 

the first time it was scanned (in March), the code was po151. this time, the guy didn't give me a code number. so i called them back and he thinks it was po136 or po137. now i can't get it scanned again because the light just went off.

 

You can still get it scanned. Codes are probably still saved on the computer.

I'll get my code book once I get a chance.

 

what year and motor? the main computer will save trouble codes. newer obd2 will also save potential codes. ie when the issue only happens once for a short time.

 

its a 98 ss with the 5.7L. i thought the guy told me the scan wouldn't work if the light wasn't on. I'll try to get it scanned again. thanks

 

at the top of this section you will see a sticky called how to and faq. this is found in that sticky https://camaroforums.com/forum/93-02...i-codes-57023/

 

the codes are po131,po137,po151,po174. so, its saying all sensors are bad and code 174 is rich or lean air/fuel ratio on engine bank 2. should i replace all sensors including the one i just replaced in march and hope that fixes the problem. or take it to a shop. i would hate to pay the shop to replace sensors if thats all it is since that is a simple repair. what do you think?

 

need to test the catyletic converters. may be failing. test fuel pressure, check fuel filter.

 

i changed the fuel filter last month. is there an easy way to test catyletic converters?