P0040 CEL Code

The message on P0040 is “O2 Sensor Signals Swapped Bank 1 Sensor 1/Bank 2 Sensor 1” So we swapped the connectors, still same code.
Seeing how the harness is not clearly marked (driver/passenger), except for a white stripe on two of the harness plugs, does anyone know how to tell which side is which?
The exhaust installer suggested that I use a “bungs" on the primary sensor ports. Would this help?
Has anyone seen this code caused by something upstream?
Any advice would be appreciated.
-Chris

After I cleared the code, I must have pulled the OBD Tester out without taking the key out of position 2 b/c when I drove away, the car was acting like it was running on 3 cylinders. Pulled it over, shut the car down and started it back up and it was normal again.

I am wondering if there is some sort of short in the harness which not enough voltage to/from the sensor.
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Sadly, I think these are tossed by now.


here the wiring diagram. G3/4 is the right upstream, G3/3 is the left upstream, G3/6 is the right downstream, G3/6 is the left down stream. keep in mind left is the driver's side, right is the passenger. Hope that helps

Last edited by roadtalontsi; Nov 27, 2013 at 08:58 PM.






