Evaporative Emissions System: Description
This system is designed to prevent fuel vapors from the fuel tank and carburetor from being emitted to the atmosphere. System consists of a sealed fuel tank, pressure/vacuum relief fuel cap, fuel tank vapor valve, carbon canister, purge control valve, solenoid vent valve and purge regulator valve (some models), and a thermactor idle vacuum valve (TIV).
NOTE:
Not all of these components are used on any one system, since usage depends on the calibration of the complete vehicle.