What Is a Catalytic Converter?

Catalytic Converter

Cars generate a lot of emissions while running. These emissions include fumes and gasses; and are polluters of the environment. The modern exhaust system now features a range of parts that control emissions to make cars more environmentally friendly.

A catalytic converter is an example of these parts, forming a vital component of the exhaust system.

What is a Catalytic Converter?

A catalytic converter works through chemical reactions to clean harmful gasses that pass through your exhaust system through simultaneous chemical reactions. The converter is on the underside and resembles a large metal box with two pipes.

How a Catalytic Converter Works

The converter utilizes the two pipes connected to it and the catalyst to ensure that exhaust fumes are safe. Gasses enter the converter from the input pipe that connects to the engine. These fumes pass over the metal catalyst causing a chemical reaction that instantly breaks apart the pollutants.

The less harmful products then travel through the output pipe that connects to the tailpipe and into the atmosphere. Inside the catalytic converter is a honeycomb structure within the cat housing with precious metals such as platinum, rhodium, or palladium. These metals play a critical role in reducing emissions. The two types of catalysts include:

Reduction Catalysts: These reduce Nitrogen Oxide pollution through oxygen removal. The process produces Nitrogen and Oxygen gasses which are harmless.

Oxidation Catalysts: These catalysts convert Carbon Monoxide into Carbon Dioxide by adding Oxygen.

Near the converter also lies an Oxygen sensor that tells the electronic control unit (ECU) the oxygen levels in the exhaust gasses. This sensor allows the engine to supply enough air to aid in oxidation.


Cat stripping is the process of removing the honeycomb structure within the converter to free up the space and reduce the level of restriction on the exhaust gasses. Since a converter works best at high temperatures, a pre-cat is found higher up the exhaust system to aid in emissions breakdown during start-up when the engine is running heavy.

Catalytic Converter Theft

Due to the precious metals inside, catalytic converters often get stolen. Theft occurs where there's more ground clearance. But you can take these steps to ensure your car is safe.

  • If you can't access a secure garage, park in a well-lit area near building entrances.
  • Weld the converter to the car frame to make it harder to steal.
  • Cover the converter with a metal cage to make the converter inaccessible.
  • Install a car alarm that comes with a vibration alert sensor.
  • Engrave your car's vehicle identification number to the catalytic converter to make it harder to sell the part and help to alert you when it's stolen.

If you need to learn more about how you can fit or replace an old catalytic converter, don't hesitate to give us a call today!

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