R 3500 P/U 2WD V8-454 7.4L (1989)
Evaporative Emissions System: Description and Operation
Except High Altitude
Evaporative Emission Control Schematic
The evaporative emission control system used on this vehicle is the charcoal canister storage method. This method transfers fuel vapor from the fuel tank
to an activated carbon storage canister to retain the vapors when the vehicle is not operating. When the engine is running the fuel vapor is purged from
the carbon element by intake air flow and consumed in the normal combustion process.
