Cherokee 4WD L6-242 4.0L VIN S MFI (1992)
Purge Control Valve: Description and Operation
Canister Purge Operation
Air Cleaner Venturi
PURGE SHUTOFF SWITCH and AIR VENTURI
The evaporative canister is equipped with a purge shutoff switch that controls canister purge operation. The switch is open when manifold vacuum
is applied to it. The air cleaner contains a venturi in the air cleaner assembly as a purge line vacuum source.
The venturi effect increases the speed of the intake air flowing by the slots in the venturi wall. This creates a low pressure area around the slots.
When the purge shutoff switch is open, vapors from the canister are drawn through slots and into the airstream flowing through the venturi. The
vapors pass through the intake manifold into the combustion chambers where they are consumed during combustion.
