Emission Control System
Positive Crankcase Ventilation System
Description
The Positive Crankcase Ventilation (PCV) system is
designed to prevent blow-by gas from escaping to the
atmosphere. The PCV valve contains a spring-loaded
plunger. When the engine starts, the plunger in the PCV
valve is lifted in proportion to intake manifold vacuum and
the blow-by gas is drawn directly into the intake manifold.
PCV HOSE
BLOW-BY VAPOR
FRESH AIR
PCV VALVE
Inspection
1 Check the crankcase ventilation hoses and connec-
tions for leaks and clogging.
BREATHER
PIPE
2. At idle, make sure there is a clicking sound from the
PCV valve when the hose between PCV valve and
intake manifold in lightly pinched with your fingers or
pliers.
If there is no clicking sound, check the PCV valve
grommet for cracks or damage. If the grommet is
OK, replace the PCV valve and recheck.
PCV VALVE PCV HOSE
Gently pinch here
BREATHER HOSE
FRONT OF
VEHICLE
Positive Crankcase Ventilation System
Description
The Positive Crankcase Ventilation (PCV) system is
designed to prevent blow-by gas from escaping to the
atmosphere. The PCV valve contains a spring-loaded
plunger. When the engine starts, the plunger in the PCV
valve is lifted in proportion to intake manifold vacuum and
the blow-by gas is drawn directly into the intake manifold.
PCV HOSE
BLOW-BY VAPOR
FRESH AIR
PCV VALVE
Inspection
1 Check the crankcase ventilation hoses and connec-
tions for leaks and clogging.
BREATHER
PIPE
2. At idle, make sure there is a clicking sound from the
PCV valve when the hose between PCV valve and
intake manifold in lightly pinched with your fingers or
pliers.
If there is no clicking sound, check the PCV valve
grommet for cracks or damage. If the grommet is
OK, replace the PCV valve and recheck.
PCV VALVE PCV HOSE
Gently pinch here
BREATHER HOSE
FRONT OF
VEHICLE