When a proper maintenance schedule is followed, cars today can easily reach 200,000 miles. It’s when routine maintenance is not done that problems occur. An item of maintenance that many people don’t think about is cleaning the carbon build-up from the engine.

Carbon build-up looks like a thin layer of black soot, and is a naturally occurring by-product of a combustion engine and is especially prevalent in direct injection systems. This build-up can result in stalling, lack of power, poor acceleration, lowered gas mileage, excessive emissions, and hesitation Check Engine Lights and even bent valves if left long enough. These things occur because the carbon build-up coats the sensors of the vehicle and the back of the intake valves which makes it so the computer cannot control the air/fuel mixture properly. This all can, ironically, lead to even more carbon build-up.

There are a handful of things that can lead to excessive carbon build-up on your vehicle’s engine. Things such as:

  • Proper running GDI engines, call if you aren’t sure if you have one
  • Contaminates in low-grade gasoline
  • Internal Oil leaks
  • An air/fuel mixture that is too rich
  • Many short driving trips
  • Excessive idling
  • A bad PCV valve

Which vehicles are most susceptible to carbon-build up problems?

Cars that use gas direct-injection (GDI) systems are at risk more than others. Owners of the following cars should have them inspected for excessive carbon build-up on a regular basis to avoid further problems down the road.

  • Many vehicles manufactured after 2012 including Asian, European and Domestic , although there are several vehicles manufactured earlier that have GDI fuel systems.
  • Mini Cooper
  • Audi
  • Some VW models
  • Some BMW models

Excessive carbon build-up can be reduced by having your vehicle’s intake and fuel system cleaned. A cleaning mixture can be flushed through the intake and  fuel system to extricate the carbon and return your vehicle to its optimum running condition. Some parts of the system, such as the mass air flow sensor, might need to be removed and cleaned by hand.

The benefits to having excessive carbon build-up removed are as follows:

  • Increased engine longevity
  • Improvement in vehicle emissions
  • An increase in the vehicle’s fuel economy
  • Restoration of lost power
  • Ease of drivability
  • A noticeable difference in engine smoothness

If you have a GDI engine, just call us if you are not sure, you should have the intake and fuel system de-carboned every 25,000 to 30,000 miles. For other vehicles an Intake and fuel system service should be performed every 50,000 to 60,000 miles depending on how you drive.  These maintenance items are ones that no one argues will save you much more than it cost you.  

Keeping your engine clean and deposit-free will help keep your vehicle running with the best fuel economy, drivability, and power for miles and miles to come; as well as ensure lower exhaust emissions, and provide you with optimal engine reliability. When is the last time you spoke to your mechanic about carbon build-up?

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