PCV System: Description

Vehicles use crankcase ventilation systems to prevent blow-by gases from reaching the atmosphere. The gasoline system consists of a PCV valve with oil screen, manifold calibrated jet (orifice), air cleaner orifice, and connecting hoses.

Turbocharged models have a hose from the valve cover to the intake tube of the turbocharger so that the vapors recirculate into the engine to be burned. A connection between the lower crankcase, valve cover and the air intake connecting hose prevents pressure build-up.

Diesel models have a hose from the valve cover to the intake manifold that recirculates crankcase vapors. Turbo diesel models recirculate blow-by gases through a main hose from the valve cover cap to the air filter inlet, and a secondary hose from the valve cover cap to the turbocharger air inlet.