EMISSION CONTROL
ENGINE AND EMISSION CONTROL17-8
VACUUM HOSE INSTALLATION
M1173007200107
1. When connecting the vacuum hoses, they should
be securely inserted onto the nipples.
2. Connect the hoses correctly, using the vacuum hose piping diagram as a guide.
CRANKCASE EMISSION CONTROL
SYSTEM
GENERAL INFORM ATION (CRANKCASE
EMISSION CONTROL SYSTEM)
M1173005000237
The crankcase emission control system prevents
blow-by gases from escaping inside the crankcase
into the atmosphere.
Fresh air is sent from the air cleaner into the crank-
case through the breather hose.
The air becomes mixed wi th the blow-by gases
inside the crankcase.
The blow-by gas inside the crankcase is drawn into
the intake manifold through the positive crankcase
ventilation (PCV) valve.
The PCV valve lifts the plunger according to the
intake manifold vacuum so as to regulate the flow of
blow-by gas properly.
In other words, the blow-by gas flow is regulated dur-
ing low load engine operation to maintain engine sta-
bility, while the flow is increased during high load
operation to improve the ventilation performance.
SYSTEM DIAGRAM
AK204365
Air cleaner
Air
Ventilation hose Breather hose
PCV valve
AB
