Evaporative Emissions System - VOLKSWAGEN: Description
Volkswagen activated charcoal filter 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, (expansion chamber is built into fuel tank on 1971 Type 2 models), an activated charcoal canister, and a series of vent lines which interconnect the components between the fuel tank and the carburetor air cleaner. A pressure line, used to purge the system, is connected between the engine blower assembly and the charcoal canister.