Positive Crankcase Ventilation (PCV)
WARNING: This page is about a different car, the 1995 Plymouth Voyager, 1995 Plymouth Grand Voyager, 1995 Dodge Grand Caravan, and 1995 Dodge Caravan. However, it is still accessible from the selected car via links, so may be relevant.
All gas engines, except 8.0L engine, use a closed crankcase ventilation system with a Positive Crankcase Ventilation (PCV) valve. A closed engine crankcase breather/filter, with a hose connecting it to air filter housing, provides source of air for system. Crankcase blow-by gases are removed from crankcase through PCV valve with manifold vacuum. These gases are introduced into incoming air/fuel mixture and become part of the calibrated mixture.