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The catalytic converter is an important component of the exhaust system which works to change harmful pollutants in to less harmful gases and water vapour to reduce emissions.

Since 1993 it has been a legal requirement for all petrol cars to be fitted with a catalytic converter. This also became compulsory for diesel cars in 2001.

Issues with your catalytic converter can increase harmful emissions and decrease the efficiency of your engine.

How Does a Catalytic Converter Work?

Exhaust gases enter the catalytic converter straight from the engine and are broken down by way of catalysed chemical reactions. Pollutants such as carbon monoxide and hydrocarbons are converted in to nitrogen and oxygen, which are much less toxic for the environment. These less harmful gases will then be funnelled away from the vehicle via the exhaust pipe.

Problems with Catalytic Converters

Catalytic converters are designed to offer a long and thorough service life, however, they could still be subject to damage. The most common catalytic converter faults include:

  • Excessive unburnt fuel in the exhaust can cause the catalytic converter to drastically heat up which can cause damage to the catalytic converter, resulting in lower efficiency.

  • Using the wrong oil in your vehicle could damage the catalytic converter as heavier viscosity oil produces more vapours than lighter oil. Partially-burned contaminants that enter and pass into the catalytic converter greatly raise the converter temperature too.

  • Damage to the catalytic converter can cause components to break and block the exhaust flow which could cause the engine to overheat, reduce exhaust function and increase fuel consumption.

  • Too many short trips at low speeds can also damage catalytic converters as they require longer journeys to reach operating temperature to clean and regenerate. Infrequent driving or not driving far enough may mean the converter will fail. Vehicles that get only intermittent use commonly have this problem.

If you suspect that there may be a problem with your catalytic converter it is important that you have it checked over by a specialist.

Visit your local Merityre Specialists branch for a FREE exhaust check or make an appointment at one of our MOT testing branches which can offer catalytic converter testing.

Merityre Specialists also sell and fit a comprehensive range of catalytic converters for all makes and models of cars. All our new catalytic converters come with fitting kits and a two-year warranty.

Find Your Nearest Merityre Specialists Branch