System Overview
Note. The vehicle emission vacuum routing diagrams are contained in the Description and Operation subsection of Evaporative Emissions. Refer to EVAPORATIVE EMISSIONS .
Note. Do not permanently remove or render inoperative any part of the vehicle emission control system including related hardware. Failure to comply may violate applicable state and federal laws.
The crankcase ventilation system gathers blow-by vapors from the crankcase and returns them to the intake manifold and air cleaner for combustion.
System Operation
During high intake manifold vacuum situations the blow-by pressure flows through the crankcase pressure regulator and is returned to the intake manifold through the crankcase vent oil separator hose. During low intake manifold vacuum situations the crankcase pressure regulator restricts flow to the intake manifold causing blow-by pressure to flow through the valve cover vent hose to the air cleaner.
Refer to ELECTRONIC ENGINE CONTROLS for more information.