What causes the Catalytic Converter to get clogged?

The catalytic converter is a component of the exhaust system that is essential to controlling vehicle emissions. It does so by converting toxic pollutants in the exhaust gases to less toxic pollutants and water, this is done by a oxidation and reduction method. When a catalytic converter fails it is essential it is immediately replaced.
catalytic_converter_smallThe process of converting exhaust gas toxic pollutants is a sophisticated one. The core of the converter is a ceramic monolith with a honeycomb filter structure. There is a film of precious metal that’s on top of the monolith which at high heat intercepts and decompose the toxins as they travel through the converter.


catalytic_converterbreaking_up_smallManufacturers claim that a catalytic converter is designed to last the lifetime of the vehicle however it’s now common knowledge that they don’t and replacing the converter at least once during the lifetime of vehicle is to be expected.
Why? The Catalytic Converter must be temperatures of approximately +400°C to be effective. It takes an average of 10 miles driving to get the converter to this temperature, but with in-excess of 50% of journeys in the UK falling short of this 10 mile minimum journey requirement the converter doesn’t get up to temperature often enough. So, by nature of being a filter the carbon deposits traveling though the converter will eventually build up and start to clog the converter.

First signs of such an issue will manifest with excessive fuel consumption and loss of engine performance but as this occurs over a period of time it usually goes unnoticed by most until there are bigger problems

Cleaning your Catalytic Converter?

There are numerous ways to clean or replace the Catalytic Converter with varying prices.

catalytic_converter_opened_smallThe costliest option is a complete replacement part. Most mechanics will recommend this – Why? Because they’ll earn a profit from the part and it’s a quicker job for them. The price of a EGR valve varies on average between £250 and £1,000 plus labour for fitting. NOTE: Some vehicles have two Catalytic Converters, in these instances both should be replaced at the same time making the bill for replacement much larger!

The moderately expensive alternative is to replace the Catalytic Converter with a ‘straight pipe’ effectively removing the converter system from the vehicle. Some choose to do this for performance purposes however for road vehicles this will invalidate the vehicles ability to pass MOT emissions tests so we do not recommend this option. Prices for such a conversion start from around £200 including labour.


Motorcycles: £74.99 – £104.99

Cars (>5,000cc £10 extra): £89.99 – £149.99

Light commericals: £119.99 – £169.99

HGV’s and all others: POA

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CarbonCleaning Catalytic Converter cleaning

image010If your vehicle requires professional intervention to unclog the Catalytic Converter there is no better alternative.

Starting at just £89.99 (including FREE before and after OBD Diagnostic tests) our Carbon Cleaning method is the least expensive.

The advantages are:-

  • Our Mobile Carbon Cleaning Technicians come to you
  • Potentially no expensive parts
  • No disassembly is required so no expensive labour
  • Completed in just 30 minutes so no having to leave your vehicle with the professionals
  • We are fully insured to compete this service at roadside or wherever your vehicle is located

As a preventative measure against clogging of the Catalytic Converter we recommend treatment every 15,000 miles

Thanks to the specially designed hydrogen treatment Carbon Cleaning is the breakthrough alternative eliminating the need to replace expensive parts.