That rhythmic knock under the hood could mean five very different things.

KNOCK, knock, knock, knock. No it's not the neighbour at the door. It's the disturbing sound of piston slap coming from your car or truck's engine. Is it a problem? Maybe -- it depends on whom you ...

One of the last noises you want to hear from under the hood of your car is a knocking sound. If you're familiar with engine knocks, you might immediately imagine having to pay thousands of dollars to ...

Question: I have a 2001 Chevrolet Lumina with 48,000 miles on it, and a 3.1-liter V-6 engine. When the engine is cold, I can hear a knock, which sounds like a rod. When the engine warms up, the knock ...