Crankcase Emission Control System; General Information; System Diagram - Mitsubishi Electric Lancer Evolution-VII Workshop Manual

17-8
ENGINE AND EMISSION CONTROL -

CRANKCASE EMISSION CONTROL SYSTEM

GENERAL INFORMATION

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
crankcase through the breather hose. The air
becomes mixed with the blow-by gases inside the
crankcase.
The blow-by gas inside the crankcase is drawn
into the intake manifold through the positive

SYSTEM DIAGRAM

Emission Control System
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 during low load engine
operation to maintain engine stability, while the flow
is increased during high load operation to improve
the ventilation performance.
Breather hose
Ventilation hose
PCV valve