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.

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 ...

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 ...

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 ...

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 ...

Over time and miles, your car might start to slow down. It might not accelerate as quickly as it once did; the engine may not run as smoothly as you remember, or the fuel economy may dip—but ...

You’re walking down the aisle of your local auto-parts store and you happen to notice the shelf full of fuel-system cleaners. They might be nestled between oil additives and those bottles of goo ...

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, ...