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.

Add Yahoo as a preferred source to see more of our stories on Google. Fuel injectors don't just deliver fuel. They meter it, shaping the spray so the air-fuel mixture burns in the way the engine wants ...

Fuel injectors can get gummed up with dirt and fuel residue over time. Photo credit: David Traver Adolphus / Autoguide.com. Over time and miles, your car might start to slow down. It might not ...

Gasoline direct injection, or GDI, is one of the most crucial bits of technology in the modern internal combustion engine. In engines equipped with GDI, highly pressurized gasoline is sprayed directly ...

There are many things that can degrade your vehicle's performance over time, from a dirty air filter and low tire pressure, to fouled spark plugs and worn out plug wires. However, nothing will rob ...

While fuel-injector cleaning is often recommended by shops and dealer service centers, it probably isn’t necessary unless it’s correcting a running problem. In many cases, just using a quality ...

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 ...

Valve gunk is nasty stuff that comes from the toxic vapor of steam, oil, gasoline and hydrocarbons circulating around the inside of your engine. A normal process of combustion in any gas powerplant, ...

Fuel injectors don't just deliver fuel. They meter it, shaping the spray so the air-fuel mixture burns in the way the engine wants it to. When deposits build up, injector fuel flow can decrease and ...