When I took it to the repair shop, the mechanic said there was a severe carbon buildup and suggested either trying a fuel ...

Modern fuel stations and auto stores are filled with small bottles of additives and so-called fuel improvers, all promising ...

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.