Carbon Cleaning

Intake Manifold Walnut Carbon Blasting/Vacuum

At Racing Technik we are the Official and only Carbon Doctor Branch in Western Cape. Carbon Doctor procedure utilise walnut carbon blasting/vacuum process as it is both cost and time affective guaranteeing the shortest turnaround in order to get the vehicle back on the road. Other methods currently used necessitate the use of strong chemicals and metal brushes that damage piston rings and valve stem seals, this is especially applicable to spray-in high revving products such as Seafoam. This unorthodox method requires the inlet to be soaked overnight creating both a time delay for the customer as well as facing corrosive risks on aluminium components. We offer walnut carbon blasting/vacuum services that have proved itself as the most (cost) efficient method worldwide which was designed, introduced and approved by BMW.

With the all-new direct injection motor technology as used in petrol and diesel engines, carbon deposits builds up on the inner walls of the intake system due to emission control devices such as exhaust gas recirculation (EGR) valves and the use of low viscosity engine oils. This results in random misfire codes stored in the ECM. With the fuel injector now located directly in the combustion chamber, there are large increases in horsepower and fuel economy. The downside to this is that there is no fuel keeping the intake valves clean and cool. Over time these engines will progressively become contaminated with carbon, restricting air flow into the engine & negatively affecting the performance of your engine.

Our Gallery

Carbon Cleaning is suitable for the following vehicles:

  • Audi 2.0T from 2005-
  • Audi 1.8T from 2009-
  • VW 2.0T from 2005-
  • VW 1.8T from 2015-
  • Audi 1.9 and 2.0TDI 2003-
  • VW 1.9 and 2.0TDI 2003-
  • Audi S4/S5/A6 etc. V6T 2009-
  • Audi V8 FSI (R8/S6/S5/RS4/RS5/Q7 etc.) 2005-
  • VW Touareg/Audi Q7 V6 FSI 2011-
  • BMW N54/N55 (any vehicle e.g.: x6/x5/3/1/5 in E and F series) 2006-
  • Mini Cooper S (All derivatives: clubman, JCW etc.) N14/N18 2006-
  • VW/AUDI 1.4 TSI 90kw (A1, A3, G6 etc.) 2009-

Also suitable, but less frequent requests:

  • Range Rover Evoque Si4/TD4
  • Ford focus ST3/RS
  • Ford Fiesta ST2
  • Audi RS3/RS Q3/ TTRS 2008-

Frequent requests deemed un-profitable:

  • BMW N63/S63/S63TU
  • BMW 320/330d
  • Audi RS6/7 V8 TFSI
  • Polo GTI 1.4 TSI
  • VW/Audi 1.4 TSI 118kw (turbo and supercharged)


All Direct injection vehicles will have carbon build up. Best is to get the car in and confirm manifold access and profitability.

Intake valve cleaning is an absolute must approximately every 50k kilometres if you want your engine to produce full power or think about tuning and remapping your car. Certain vehicles including the Audi RS4 requires shorter cleaning intervals due to PCV design, condition, compression ratio and turbo seal condition.

As unfortunately this carbonising effect is an inevitable by-product of direct injection, it cannot be prevented. The use of additives in the fuel itself is useless, as the fuel does not come into contact with the intake tract or the valves at all; the use of water/methanol injection may slow down the carbonising somewhat (depending on where the methanol is injected and provided it is not yet completely vaporised when it reaches the valves), but cannot prevent it either. The cleaning of the intake valves by using Seafoam or similar products which are injected directly into the charge pipe has been discussed extensively, but equally this method is not very efficient as the carbonising is usually too persistent to be removed by this method.

Carbon Build Up Symptoms

There are several issues that can develop due to carbon build up:

  • Rough Idle
  • Detonation
  • Leaking valves
  • Power loss
  • Misfires
  • Engine check lights

Our Cleaning Procedure

The walnut blasting is done without major engine striping, we remove the intake manifold to gain access to the valve stems. The engine is then rotated ensuring the valves that are cleaned are fully closed to prevent any debris entering the cylinder bores. The special cleaning system fits perfectly into the intake port, linked to an industrial vacuum and the walnut blasting equipment. Crushed walnut shell granules about 0.5 millimetre in diameter are then blasted directly on the valves and intake port, the walnut shells are hard enough to remove the carbon but not hard enough to damage the valves or intake port. The vacuum cleaner sucks out both the carbon & walnut shells. This process is repeated several times until clean and repeated for each intake.

Indicative Pricing per Vehicle

4 Cylinder Cars (TFSI/TSI/FSI)


R3737.00 incl VAT

+/- 12 Hours

6 Cylinder Cars (35i/Lexus/TFSI)


R4542.00 incl VAT

+/- 16 Hours

8 Cylinder Cars   (RS4/S5/RS5/FSI)


R7020.00 incl VAT

+/- 24 Hours

HGV, Trucks, Plant, Marine, Generators, Light Aircraft


To reserve an appointment please call or send an email, we usually require approx. 1-2 working days’ notice for availability.