Wrangler 4WD L4-150 2.5L VIN P MFI (1998)
Positive Crankcase Ventilation: Description and Operation
CRANKCASE VENTILATION SYSTEM
Fig. 4 CCV System
All engines are equipped with a Crankcase Ventilation (CCV) system (Fig. 4). The CCV system performs the same function as a conventional
PCV system, but does not use a vacuum controlled valve.
A fitting on drivers side of cylinder head (valve) cover contains the metered orifice. It is connected to manifold vacuum.
When the engine is operating, fresh air enters the engine and mixes with crankcase vapors. Manifold vacuum draws the vapor/air mixture through
the fixed orifice and into the intake manifold. The vapors are then consumed during combustion.
