Catalytic Converter: What You Need to Know

The catalytic converter is part of your car's emissions systems, and it plays a crucial role.

It's located upstream of the muffler, close to the engine, and it changes environmentally damaging pollutants in the exhaust stream into more benign gases. Under extreme heat, precious metals in a honeycomb structure catalyze the chemical reactions; they make today's vehicles dramatically cleaner than older vehicles.

How do I know when it's time to replace my catalytic converter?
Catalytic converters can be damaged by road debris, contaminated by engine oil or coolant, or become clogged and restrict exhaust flow. Among the signs of a bad catalytic converter are sluggish performance, dark exhaust smoke or the smell of rotten eggs in the exhaust. A misfiring spark plug, faulty oxygen sensor, or other fuel or emissions-related problem can cause a catalytic converter to overheat.

How often should I replace my catalytic converter?
It often lasts 10 years or longer and should be replaced only when needed. It can become clogged, physically damaged, or contaminated by oil or engine coolant. Occasionally it might even be stolen by thieves looking to get the precious metals inside. Some symptoms can be caused by other parts of the emissions system, so a mechanic should diagnose the entire system before replacing the converter.

Why do I need to change my catalytic converter?
Catalytic converters need to be replaced only if they become clogged or damaged and can't function properly. They're expensive to replace, so they aren't considered a regular maintenance item.

How much should I pay?
The cost of repairs can depend on where you are as much as it does on what you need fixed. To get an estimate for your repair, go to our estimator, plug in your car's year, make and model information, add your ZIP code, and choose the repair you need. We'll give you a range for what your repairs should cost in your area.