How Often Should I Replace My Catalytic Converter?

img 502282511 1456184842261 jpg photo by Evan Sears

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.

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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.’s Editorial department is your source for automotive news and reviews. In line with’s long-standing ethics policy, editors and reviewers don’t accept gifts or free trips from automakers. The Editorial department is independent of’s advertising, sales and sponsored content departments.

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