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Q: check engine light O2 sensor already replaced same codes still popping up after replacing old O2 sensor

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I went to AutoZone after seeing a check engine light on and got a diagnostics check on my check engine light it said I have a faulty O2 sensor bank 1 sensor 2 to replace so I replaced it got my codes cleared even reset the codes by disconnecting the battery and drove over a hundred and fifty miles already I still have the check engine light on I went to AutoZone and got another diagnostic check and the same code is popping up still saying I need a new O2 sensor that bank 1 sensor 2 is faulty what should I do what else could be the problem if I have a brand new fitted O2 sensor in there already bank 1 Sensor 2 is the downstream O2 sensor on the Cadillac converter please someone help me what could be the problem

My car has 98000 miles.
My car has an automatic transmission.

Hi there. What you received from the parts store was a code retrieval, not a diagnostic. The codes are set when a fault is detected against normal operating parameter. The computer does not know what caused the fault, only that the fault meets the criteria for this code to set. There could be a problem in the wire harness, converter, or the ECM. The code and data are needed to properly assess the direction that a diagnosis needs. I strongly suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a check engine light inspection.

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