P0133, where to start?
 

Got this code and did a search here on the forum and turned up only a couple results, so I assume its a rare code. I swapped the new AC Delco O2 sensors from passenger to driver and cleared the code but it came back. No worries, I assume its a wiring problem. Which wires do I need to start testing on the wiring harness and what should the results be? If I am heading in the wrong direction on fixing this problem well by all means, turn me around! I have found threads about testing the O2 sensor, but I THINK I need to be testing the wires going to the O2 sensor, so that is the measurements I need. Rear O2s deleted if that helps. Thanks everyone!

Re: P0133, where to start?
 

This thread I found sounds like the best info. Maybe you already read it, but if after headers installation, it could be your problem.
https://www.camaroz28.com/forums/lt1...nstall-416735/

Re: P0133, where to start?
 

I put on long tubes way before I bought these sensors. The code stays on bank one even when I switch sides with the sensors.

Re: P0133, where to start?
 

That's odd, because the P0133 is specifically for a lazy sensor - slow rich-to-lean/lean-to-rich signal transition rates. It's hard to see how this could be caused by the wiring, or some operating condition specific to that bank. Did you clear the codes before you switched the sensors side-to-side?

The speed of the sensor's reaction to O2 level changes might be affected by loss of the heating element. But a circuit problem on the heater would set P0135. Might be worth verifying you have 12V to the heater circuit, at the O2 sensor harness connector.

Re: P0133, where to start?
 

I am pretty sure I cleared the code and switched sides with the sensors. Started getting the code after h/c swap and dyno tune. The sensors are brand new, I bought them specifically for the dyno tune. It did run off the charts rich before the tune, I did drive it to the shop like that. Any way that drive coulda ruined the o2s on the trip down there? Should I buy a set of o2s and give that a try?
Oh, I already forgot about checking the voltage. Which wire is for the heater?

Re: P0133, where to start?
 

But if you "ruined" the O2 sensors, the code would follow the O2 sensor to the other side of the engine.

Re: P0133, where to start?
 

Ahh, yes you are correct. Wasnt thinking that all the way through.