Engine Running

Fuel vapors adsorbed in the canister(s) are drawn into the intake manifold through the purge control valve and an orifice. The thermo valve controls the purge control valve. When coolant temperature reaches predetermined value, purge control valve is opened. Valve remains closed until predetermined temperature value is reached. Fuel vapors adsorbed in the carbon element of Pickup models are led into the carburetor. Carburetor bowl vapors flow into the carburetor through bowl vent valve.