Symptoms of a Bad or Failing Catalytic Converter

catalytic converter

A catalytic converter is an exhaust emissions component that works to reduce vehicle emissions and pollution. It is a metal canister that is installed in the exhaust system. It is filled with a chemical catalyst, usually a platinum and palladium mixture, and helps to convert the vehicle’s emissions into non-harmful gasses. Usually a faulty catalytic converter will produce a few symptoms that can alert the driver that service may be required.

1. Reduced engine performance

One of the first symptoms commonly associated with a bad or failing catalytic converter is a reduction in engine performance. The catalytic converter is built into the vehicle’s exhaust system, and as a result, can affect the performance of the engine if it develops any problems. A clogged converter will restrict exhaust flow, while a cracked one will leak. Both can negatively affect engine performance and can cause a reduction in power and acceleration as well as fuel economy.

2. Rattling noise

Rattling noises are another symptom of a bad or failing catalytic converter. If a catalytic converter becomes old or damaged internally from excessively rich fuel mixtures, the catalyst coated honeycombs on the inside of the converter can collapse or break apart causing a rattle. The rattle may be more obvious when starting the vehicle, and will get worse over time.

3. Check Engine Light comes on

A bad or failing catalytic converter can also cause an illuminated Check Engine Light. The oxygen and air fuel ratio sensors that modern vehicles are designed with monitor the efficiency of the catalytic converter by monitoring the gas levels in the exhaust. If the computer detects that the catalytic converter is not operating correctly, or not catalyzing the exhaust gases properly, it will set off the Check Engine Light to alert the driver that there is a problem. A Check Engine Light can also be activated by a variety of other problems, so it is recommended to have the vehicle scanned for trouble codes to be certain of the issue.

The catalytic converter is one of the most important emissions components found on modern vehicles. Without it the vehicle may produce excessive emissions and have trouble passing the emissions tests that are required in some states. If you suspect that your catalytic converter may be having a problem, have the vehicle inspected by a professional technician, such as one from YourMechanic to determine if the car will need a catalytic converter replacement.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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