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Q: Faulty O2 sensor

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I failed my inspection due to a faulty O2 sensor. The Check Engine light is not on though, so I am not sure if it's a leaky hose from the exhaust system causing the error.

Hi, it is possible for the O2 sensor to not turn on the Check Engine Light if it is failing slowly. It’s also possible for leaks to occur, which can throw off the sensors readings. I would recommend having a technician inspect your exhaust system.

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