You'll be hard-pressed to find an overhead valve — also known as a pushrod — engine in anything outside of a General Motors LS/LT V8 or one of Stellantis' Hemi V8s. Everything else is a part ...

As a result of that combustion, a lot of gasses are produced around the engine. One such vital part that helps deal with gas that finds its way into the crankcase is the PCV valve — or positive ...

The valve is an inexpensive, easily replaced example of the dozens of parts that can elicit a check engine light and associated vexing investigation. It can also be the source of oil leaks.