War Prayer

I did a quick search and wasn't able to find an explanation. I purchased the car with the exhaust already installed. Kooks LTs and ORY. I have been trying to solve a p1133 code issue, and when I put the car up to start switching things around I realized the driver's side header has two O2 sensors and the passenger side has one. The y pipe has plugs in the bungs and no cats obviously so I guess I was expecting one upstream (sensor 1) on each side.

Am I missing something obvious? I am new to the LS platform cars having build an older (pre-emissions) small block car. Thanks in advance.

EDIT: Could this be a sensor for a wideband gauge?

LLLosingit

iTrader: (4)

One would be for the factory computer the other was likely for a separate aftermarket wideband.

War Prayer

Thanks, that makes sense the car does have an AFR gauge in the pillar pod but it doesn't seem to work. Is there any easy way to tell which is the factory emissions sensor? My plan is to swap banks and see if the code follows.

LLLosingit

iTrader: (4)

If you follow the wires the one for the factory computer will go into a larger part of the harness. The aftermarket wiring would stay the same size and go through the firewall somewhere.

War Prayer

Much appreciated.

bigsapper

The sensor on the driver's side that looks exactly like the one on the passenger side will be the factory narrow band sensors.

I had a wideband & gauge setup (AEM). The gauge shorted out after a year and the whole thing was worthless without a new gauge.

Currently using a gaugeless setup that just plugs into my logger (HPT).