Decarbonisation or engine carbon cleaning simply refers to the process of removing carbon deposits in the engine. Carbon build-ups are inevitable in vehicle engines due to improper burning of fuel, substandard fuel quality and general build up with age. Excess carbon deposits itself as soot around exhaust valves, in the exhaust, on the cylinder head, on the piston, O2 sensors and on the intake and exhaust manifolds.

With time, especially in older cars, this carbon build up can lead to valves not closing properly, spark plugs fouling, O2 sensors failing and other issues. Some of the first symptoms of carbon build up will include a lack of
power and low mileage from the car. Severe cases will also show up as black soot deposits spilling out of the exhaust. Decarbonisation is a preventive maintenance procedure and should be done after around 50,000km before the vehicle starts developing these symptoms.

Removing carbon deposits from vehicle engines can either be mechanical (physical) or through chemicals. The mechanical procedure involves removing the cylinder head, intake and exhaust valves and also the exhaust pipe thoroughly cleaned and then scraping off carbon deposits from the top of the pistons, the combustion chamber and other components. In doing these, many things can go wrong if handled by an incompetent mechanic. Therefore, most vehicle owners go for chemical decarbonisation. Using chemicals to dissolve excess carbon build-up in your engine is far less expensive and less risk is involved.

Some benefits of decarbonising your engine includes: restored lost power, improved combustion efficiency, smoother idle, improved MPG, improved fuel economy and better acceleration.