RAM 1500 Truck 4WD V8-5.9L VIN Z (2002)
Positive Crankcase Ventilation Valve: Description and Operation
Operation
Fig. 12 Typical Closed Crankcase Ventilation System
The PCV system operates by engine intake manifold vacuum. Filtered air is routed into the crankcase through the air cleaner hose. The metered air,
along with crankcase vapors, are drawn through the PCV valve and into a passage in the intake manifold. The PCV system manages crankcase pressure
and meters blow by gases to the intake system, reducing engine sludge formation.
The PCV valve contains a spring loaded plunger. This plunger meters the amount of crankcase vapors routed into the combustion chamber based on
intake manifold vacuum.
Fig. 13 Engine OFF Or Engine Backfire - No Vapor Flow
When the engine is not operating or during an engine pop-back, the spring forces the plunger back against the seat. This will prevent vapors from
flowing through the valve.
