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 ...

The original designs of a PCV valve were invented during WWII to help tanks drive in water when their engines were submerged. Before the PCV valve was invented, engines would use ‘downdraft’ o ...

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.