Fuel Evaporation System: Description

Porsche fuel evaporation control system is designed to prevent fuel vapors from being emitted into the atmosphere. The system consists of a non-vented fuel tank filler cap, an expansion chamber, an activated charcoal canister, a purge valve, a vent valve, 2 control valves on 944 and a series of vent lines interconnecting components between fuel tank and air cleaner.

On air-cooled models, a pressure line, used to purge the system, is connected between the engine blower assembly and charcoal canister.