Function

Catalytic converters remove harmful elements from automotive exhaust by forcing the fumes to pass over metallic catalysts, including platinum, rhodium and palladium, which neutralize the toxins and transform them into relatively safe components. The entire casing of the converter is constructed of stainless steel. All of these expensive metals make a catalytic converter a costly piece of equipment.

Cars with Dual Exhaust

While most production cars have only one catalytic converter, some do come with two. Cars with dual exhaust often have two catalytic converters — one for each set of pipes running from the headers to the rear of the vehicle.

Cars with Two In-Line Catalytic Converters

Newer high-end vehicles are now coming equipped with two catalytic converters as part of an even more stringent emissions program. The first converter breaks down the exhaust as normal, while the second acts both as a filter for tiny particles and a pump which releases a chemical mixture that further reduces any harmful gases which may have escaped the first converter.

What Are Potential Issues With a Catalytic Converter?

Catalytic converters often last for 10 years or more, but they can become contaminated, clogged, overheated or physically damaged — leading to sluggish engine performance and, eventually, engine shutdown.

One potential contaminant is leaded gas, which can destroy the catalysts, although it is rarely found in the U.S. Others contaminants include engine coolant, which can leak into the combustion system because of a faulty cylinder head gasket, and engine oil. Those fluids can clog a catalytic converter so that exhaust gases are restricted from passing through. Car engines are like athletes in that they require lots of oxygen. If the exhaust flow is restricted, it means less air can get into the engine and performance suffers. If the engine responds sluggishly or quits after running for a while, a clogged converter could be to blame.

Catalytic converters can overheat because of excessive amounts of unburned gas caused by a misfiring spark plug or a leaky exhaust valve. In addition, a failed oxygen sensor can cause overheating.

On many vehicles, the “cat” is located under the vehicle, and like other parts of the exhaust system, it can also be damaged by road debris or by running over a curb.

Catalytic Converter Maintenance

Among the symptoms of a bad catalytic converter are:

  • Sluggish engine performance
  • Reduced acceleration
  • Dark exhaust smoke
  • The smell of sulfur or rotten eggs from the exhaust
  • Excessive heat under the vehicle

Some of those symptoms can also be caused by other parts of the emissions system, so it’s important for a mechanic to diagnose when it’s time to replace your catalytic converter.

Following your vehicle’s recommended maintenance schedule can help delay this moment as long as possible — often 10 years or more. Keeping your exhaust, emissions and combustion systems in good shape will minimize the risk of your catalytic converter failing before its time.

Stop by Sierra Car Care today for your catalytic converter and exhaust system repair needs.