General Description

Schematic:

Fuel evaporation is a normal process in any fuel system. The purpose of the Evaporative Emission System ([1][2]EVAP) is to limit amount of fuel vapors (hydrocarbons) escaping into atmosphere. To accomplish this, EVAP system transfers fuel vapors that accumulate in fuel tank into an activated carbon storage container - EVAP canister. The EVAP canister will store these vapors until Powertrain Control Module (PCM) determines that engine is able to burn this stored fuel vapor. When PCM determines that engine is able to use this stored fuel vapor, it is pulled, or purged, along with fresh air, into intake air flow by opening purge and vent solenoids. It is then consumed in the normal combustion process.

The components that make up the enhanced evaporative emission system consist of the following:
^ [1][2]EVAP Vent Solenoid, located on upper end of fuel filler pipe, just behind right rear wheelhouse liner.
^ Fuel Tank.
^ Evaporative Emission System Canister, nested on top of fuel tank at left front corner.
^ Fuel Tank Pressure Sensor, inserted on top of fuel tank.
^ System fuel lines and hoses.
^ Evaporative System Service Diagnostic Port, located near right shock tower.
^ EVAP Purge Solenoid, located near right shock tower.