Popular Mechanics’s automotive experts outline the tools and techniques proven to smoke out even the toughest to find vacuum ...

Car engines require a lot of parts working in ... One such vital part that helps deal with gas that finds its way into the crankcase is the PCV valve — or positive crankcase ventilation.

The positive crankcase ventilation valve releases exhaust gas and unburned fuel from the engine block into the intake manifold. All engines allow some exhaust gases, unburned fuel and oil to ...

A mechanic will be able to do some tests and determine what’s causing the pressure build-up inside the crankcase. If it’s internal wear, a rebuild may be required. But if it’s a build-up of crud ...

The report added that this layout enables a more compact crankcase design, making it possible to package the new engine into cars not originally engineered for a V8, including the C-Class.