Positive Crankcase Ventilation: Description and Operation

Fig. 3 Fixed Orifice Fitting:

This engine is equipped with a Crankcase Ventilation (CCV) system. The CCV system performs the same function as a conventional PCV system, but use a fixed orifice instead of vacuum controlled valve (PCV valve).

It meters the amount of crankcase vapors drawn out of the engine. The fixed orifice fitting is grey in color.

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 engine combustion.