Why do Spark Plugs get dirty?

dirty_spark_plugsTo a certain degree Spark Plugs are designed to be self cleaning. However, when the they become dirty they will foul causing misfires, loss of power and fuel economy and increased emissions.
Different engine model require a certain specification of spark plug. As the engine runs the ceramic shell of the plugs must get hot enough that the electrode burns off any carbon deposits, oil and fuel yet not so hot that there is a risk of detonation / pre-ignition.

Long journeys and highway speeds increase engine temperature which is a good environment for spark plug self cleaning. However, short journeys and today’s ever worsening stop-start traffic is not a good thing, temperatures don’t get high enough to aid the self cleaning so deposits start build on the electrodes. Eventually this leads to failure of spark and misfires. The electricity sent to the plug form the ignition coil is short circuited, the unspent fuel/air mixture is both recirculated (through the Exhaust Gas Recirculation system) which aids and abets carbon deposit build up in other parts of the engine and the rest exits through the exhaust in the form of excessive emissions and pollution.

Cleaning your Spark Plug

There are numerous ways to clean or replace the Fuel Injectors with varying prices.new_spark_plugs

The costliest option is a complete set of replacement parts. 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 replacing Spark Plugs varies considerably and will obviously depend on how many the engine has.


clean_spark plugsThe moderately expensive alternative is to remove the plugs and manually clean them with a wire brish, this requires some mechanical skill and time. The problem is not all spark plugs are access, especially for the novice mechanic. As there are no replacement parts involved the cost of this is just the labour.


Motorcycles carbon cleaning: £74.99 – £104.99

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Discounts for carbon cleaning and DPF cleaning together from as little as £299.99

Call us for multi-vehicle discounting (as much as £50 per vehicle!)

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CarbonCleaning Spark Plug cleaning

image010If your vehicle requires professional intervention to clean the Sparks Plug 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 dirty spark plugs we recommend treatment every 15,000 miles
Thanks to the specially designed hydrogen treatment CarbonCleaning is the breakthrough alternative eliminating the need to replace expensive parts.

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