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How Often Should I Replace My Catalytic Converter?

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CARS.COM — How often should a catalytic converter be replaced? Here are some tips. The catalytic converter, which converts harmful emissions into harmless gas, often lasts 10 years or longer and should be replaced only when needed.

Related: Maintenance 101 Advice

It can become clogged, physically damaged, or contaminated by oil or engine coolant. It can also overheat. Signs of a bad converter include reduced acceleration, the smell of sulfur or rotten eggs from the exhaust, and excessive heat under the vehicle. Some of those symptoms can be caused by other parts of the emissions system, so a mechanic should diagnose the entire exhaust system of the car before replacing the catalytic converter.

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Rick Popely

Contributor Rick Popely has covered the auto industry for decades and hosts a weekly online radio show on TalkZone.com.

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