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Q: I had the catalyst converter replaced last year. Now the Check Engine Light is on again for O2 sensor. What do I do?

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I had the catalyst converter replaced last year but now the check engine light is on again for the o2 sensor and catalyst converter why am i having this issue again with the impala what could possibly be going on to cause emission failure with a fairly new replaced converter?

My car has 72000 miles.
My car has an automatic transmission.

You may want to have a professional inspect the catalytic converter. When the Check Engine Light comes on for this, it does not necessarily mean that the catalytic converter has failed. This may be related to many other things as well such as the O2 sensor making false readings or potentially a rich or lean fuel mixture being caused by something else.

To avoid any unnecessary repairs, I would recommend having one of our mobile experts come out to you to do a proper diagnostic test using a scanning tool to download the car’s trouble codes and inspect the catalytic converter.

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