Is a reflash of the ECM necessary
I have gotten a Check engine light a couple of times, and then soon after it goes off. I hae a mechanic pull the codes and it is saying that Back 1 and 2 O2 sensors are staring to fail. He suggested...
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I would say it would probably be best to replace both, if the one O2 sensor failed, its likely the others aren't far behind, so there's some logic to doing both sets, the sensors get subjected to the pretty extreme abuse (exhaust gasses, heating cooling cycles, etc..)
The computer will need to re-learn the sensors new readings, but it should figure that out in a few drive cycles, should be no need to reflash anything for that. MAYBE if the new sensors are completely different type and the computer needs to be told to look for different "signals", but that drastic of a change is pretty rare, I would ask them why they say a reflash is needed before letting them touch anything.
The computer will need to re-learn the sensors new readings, but it should figure that out in a few drive cycles, should be no need to reflash anything for that. MAYBE if the new sensors are completely different type and the computer needs to be told to look for different "signals", but that drastic of a change is pretty rare, I would ask them why they say a reflash is needed before letting them touch anything.
