E 150 1/2 Ton Van V6-4.2L VIN 2 (1997)
Evaporative Check Valve: Description and Operation
Fuel Vapor Valve (Typical)
Purpose
Fuel vapors in the fuel tank are vented through the evaporative emission valve located in the top of the fuel tank. The vapors are transmitted through a
single vapor tube to the evaporative emissions canister at the front of the vehicle. A spring loaded poppet valve provides relief ahead of the orifice to the
evaporative emissions canister.
Operation and Construction
The evaporative emission valves makes use of a small orifice and shutoff valve that tends to allow only fuel vapor, not liquid, to pass into the fuel and
vapor return tube routed forward to the evaporative emissions canister.
