F 150 4WD Pickup V8-351 5.8L VIN G 2-bbl (1984)
Bowl Vent Valve: Description and Operation
Vacuum Bowl Vent Valve
Fig. 60 Vacuum bowl vent valve
This valve, Fig. 60, used on some vehicles, is a vacuum operated on/off valve. This valve controls vapor flow from the carburetor bowl to the carbon
canister. When the engine is running, manifold vacuum closes the flow path from the carburetor bowl to the carbon canister.