Q: Would a clogged catalytic converter make a car smoke?

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My check engine light came on saying the catalytic converter was clogged and at the same time I noticed some smoke coming from the exhaust pipes and I was wondering if the two were related.

Hi, thanks for writing in. If you are getting white smoke from the exhaust of your vehicle and you have trouble codes related to the catalytic converter it is likely that your vehicle is burning oil. The oil getting into the combustion chamber due to faulty piston rings are faulty valve guide seals will end up getting oil inside the catalytic converter. The oil burns inside the combustion chamber and is exhausted through the exhaust system. Deposits from this burned oil can reside inside the exhaust system causing a clog eventually. If this is the case, I would recommend having an engine overhaul to resolve the oil burning issue as well as replacing the catalytic converter in order to resolve this issue. Here at YourMechanic, we can have a technician come to your home or office to inspect this smoke issue for you, and make or suggest the necessary repairs.

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