The other day I dropped my car off at a European specialist shop, and while I was there, a technician was working in the engine bay of a Mk7 Golf R, cleaning out carbon deposits off the intake valves.

Q: I have a 2009 VW with gasoline direct inject and a 2.0-liter turbo engine. It recently needed the intake valves cleaned (a very costly job) after just 54,000 miles. I understand many manufacturers ...

While carbon buildup happens on essentially all engines, gasoline, diesel, N/A, or boosted, it's an increased concern in GDI engines. Standard Electronic Fuel Injection features injectors higher in ...