Should O2 Sensors be changed in pairs? My 2011 GMC Sierra 1500 5.3L Flex Fuel is showing a bad O2 Sensor, bank 1, sensor 1. I've read they should be changed in pairs. If so which pair? The two same sensors, i.e, two upstream, or two downstream. Or should the two sensors in the bank both be changed, i.e., bank 1 sensors 1 and 2?
Please do not double post. Thank you.
Not really because theoretically they're supposed to last forever they're not supposed to eat themselves up of course it is GM and you have poor quality but I don't change bad one you don't need to change them in pairs they equilibrate themselves I've changed out many one out of two or one out of four in the cars are in fine
I would only change what is culprit.
Most definitely "in pairs" does not mean here "the up- and the downstream sensor of one and the same bank".
Whether or not the two upstream sensors (or two downstream sensors) shall be changed in pairs, is arguable. I personally (and unfortunately) have vast experience with replacing downstream sensors on my car, and on my car it never made any difference it I replaced them in pairs, or just the faulty one.
