Evaporative Emissions System: Description and Operation

Flexible Fuel Evaporative Emission System:

Engine view.

Flexible Fuel Canister And Tray Assembly:

Canister tray assembly.


PURPOSE
To reduce HC, the fuel vapors are vented from the fuel tank to the carbon canisters and stored there until they can be purged to the engine for consumption.

OPERATION
The fuel vapors are vented from the fuel tank through the vapor valve (located in the top of the fuel tank) through a single line to the refueling control valve. The fuel vapors are then routed through the refueling control valve to the carbon canister array (4 carbon canisters with one liter volume of carbon each). This canister array is located under the spare tire carrier on the outside of the vehicle. Purging the carbon canisters removes the stored fuel vapors and delivers the fuel vapors to the engine for consumption. With the Powertrain Control Module (PCM) controlling the Vapor Management Valve (VMV), the engine receives the correct amount of fuel vapor at operating temperature.