Engine Emission Controls

CAUTION: Do not remove any part of the engine emission control system. Operating the engine without the engine emission control system intact will reduce fuel economy and engine ventilation. This will weaken engine performance and shorten engine life.

The engine emission control system consists of the:
^ Positive Crankcase Ventilation (PCV) system.
^ Exhaust Gas Recirculation (EGR) system.

Exhaust Emission Control System
The Vehicle Emission Control Information (VECI) decal is located on the upper radiator support and shows:
^ components of the emission control system.
^ the correct vacuum hose routing.
^ the color stripe of the vacuum hoses.

Positive Crankcase Ventilation (PCV) System
The PCV system uses intake manifold vacuum to ventilate blow-by fumes from the crankcase and return the fumes to the intake manifold for combustion. The Positive Crankcase Ventilation valve (PCV valve) varies the amount of blow-by gases returned to the intake manifold based on available engine vacuum. The positive crankcase ventilation valve also prevents the entry of combustion backfiring into the crankcase.







The PCV system consists of the components as shown in the illustration.