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What is a Walnut Blasting service, and why is it important? Do not literally put walnuts in your intake, but keep reading to learn more about this service recommended for BMW and MINI owners every 30,000 miles. It is especially recommended to do this before you tune or modify your vehicle.

All direct injection BMW engines suffer from excessive carbon build up on the vehicle’s intake valves to some degree. Not to worry as this is a common issue. As carbon levels increase though, the following issues will slowly become more prominent. BMW Walnut Blasting Service

  • Poor throttle response
  • Engine Misfiring
  • Loss of fuel economy
  • Cold start idle issues
  • Flat spots in the vehicle’s power band
  • Lack of Engine Power

I am sure you are wondering why this happens to your BMW. The most common reason for the carbon build up is due to contaminants in the air that pass across the engine’s intake valves. In a multi-port injection engine, fuel is injected prior to the intake valves, which allows the fuel to clean the buildup that accumulates on the intake ports and valves. Contaminants in the air mixture are then carried into the cylinder with the fuel to be burnt.

In BMW’s direct injection engine, fuel is injected directly into the cylinder. This causes the oil and carbon contaminants to collect on the valve. Over time, the engine is slowly restricted of useable air, which is why this service is necessary. Central Avenue Automotive provides BMW cleaning services for all Direct Injection engines. The service is completed with the use of our BMW factory approved tooling, and approved crushed walnut shell media. Our service removes excess carbon build up, and will save you significantly more money than if your cylinder head was removed for cleaning.


Unfortunately there is no simple solution to prevent carbon buildup of BMW direct injection engines. Some solutions may post-pone the problem or even extend the period between services, but they will not eliminate it fully. Our Service Team will help to educate our BMW and MINI Drivers about performing this cleaning as part of a regularly scheduled maintenance program we recommend every 30,000 miles.


Central Avenue Automotive is located in Kent Washington.  Our Team of Expert BMW Technicians offer complete BMW and Mini cooper Intake Valve Cleaning services, as well as BMW and Mini Cooper Repair, Factory Scheduled Maintenance, Tuning, and Performance Upgrades for BMW and MINI coopers.