STRUCTURE AND OPERATION
ECM-29
< SYSTEM DESCRIPTION >
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STRUCTURE AND OPERATION
Positive Crankcase Ventilation
INFOID:0000000010702814
This system returns blow-by gas to the intake manifold.The positive
crankcase ventilation (PCV) valve is provided to conduct crankcase
blow-by gas to the intakemanifold.
During partial throttle operation of the engine, the intake manifold
sucks the blow-by gas through the PCV valve.
Normally, the capacity of the valve is sufficient to handle any blow-by
and a small amount of ventilating air.The ventilating air is drawn from
the air inlet tubes into the crankcase. In this process the air passes
throughthe hose connecting air inlet tubes to rocker cover. Under
full-throttle condition, the manifold vacuum is insufficient to draw the
blow-by flow through the valve.The flow goes through the hose con-
nection in the reverse direction.
PBIB2962E
PBIB1588E