Pickup 2WD L4-155 2555cc 2.6L SOHC VIN E 2-bbl (1988)
Early Fuel Evaporation ( EFE ): Description and Operation
Fig. 105 Heated air intake system
Heated intake air, Fig. 105 is used during engine warm-up to improve driveablity.
To achieve overall emission performance the carburetor is calibrated overly lean. Warmed intake air is used during warm-up to eliminate carburetor
icing and improve cold engine performance and driveablity.
The air cleaner housing snorkel is equipped with an air control valve that mixes warm air from the exhaust manifold heat cowl with cold air from the
snorkel. The air control valve is operated by a vacuum motor that actuates the air control valve. The vacuum motor is controlled by a bi-metallic spring
bleed valve which regulates the vacuum control signal.
