Dakota Quad Cab 2WD V8-4.7L VIN N (2001)
Fig. 16 High Intake Manifold Vacuum - Minimal Vapor Flow
Fig. 17 Moderate Intake Manifold Vacuum - Maximum Vapor Flow
TYPICAL PCV valves are shown in, and.
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.
During periods of high manifold vacuum, such as idle or cruising speeds, vacuum is sufficient to completely compress spring. It will then pull the
plunger to the top of the valve. In this position there is minimal vapor flow through the valve.
During periods of moderate manifold vacuum, the plunger is only pulled part way back from inlet. This results in maximum vapor flow through the
valve.
