PCV System

The PCV system uses intake manifold vacuum to ventilate blow-by fumes from the crankcase and return the fumes to the intake manifold for combustion. The 2.3L engine does this through a coolant-heated fitting. The PCV valve varies the amount of blow-by gasses returned to the intake manifold based on available engine vacuum. The PCV valve also prevents the entry of combustion backfiring into the crankcase.