Q: Check Engine Light O2 sensor slow

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My car has 110,500 km on it, and it accelerates slower than usual lately. I replaced the MAF about 2 months ago, then I disconnected and reconnected the battery. Now it runs much faster, but it only lasted for 2 weeks. I tried resetting the ECU and it didn’t help. Then the Check Engine light came on. So I took it to the repair shop and they said the O2 sensor is on the blink. I didn’t replace it yet. I just disconnected and reconnected the battery and that cleared CEL light. Now the car runs faster again. Will the car run faster if I put in a new O2 sensor? Will I have to keep disconnecting and reconnecting the battery every 2 weeks? Or will the new O2 sensor fix those problems? Thanks.

Hello. The computer reset only puts the computer in a position that it will control the fuel as if you just bought the car. As the vehicle is driven and a defective O2 sensor gives a bad input to the computer, the computer will slowly start to adjust the fuel by its input and then get to a level that it cannot compensate anymore. It will then turn on the Check Engine Light and may reduce power. Have the defective sensor replaced and clear the codes again.

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