A small gap with big importance in the performance and health of an engine - here's everything you need to know.

Last month's "How It Works" story gave you the basics of the four-stroke cycle, describing the motion of the intake and exhaust valves in relation to the piston moving up and down in the cylinder.

NHTSA is investigating 2021 model year Ford Bronco SUVs due t reports of catastrophic engine failure. The failure point allegedly stems from valves dropping into their respective cylinders and causing ...