Purpose

EVAP System Components:

IMPORTANT: A control module refers to the PCM and the VCM.

The Evaporative Emission ([1][2]EVAP) control system limits the fuel vapors escaping into the atmosphere. The EVAP transfers fuel vapor from the sealed fuel tank to an activated carbon (charcoal) storage device called the EVAP canister. The EVAP canister stores the vapors until the engine is able to use the extra fuel vapor.

When the engine is able to use the extra fuel vapor, the intake air flow purges the fuel vapor from the carbon element, and the vapor is then consumed in the normal combustion process.

The [1][2]EVAP control system can detect evaporative fuel system leaks as small as 0.040 between the fuel filler cap and the purge solenoid. The EVAP control system tests the evaporative system's integrity by applying a vacuum signal (ported or manifold) to the fuel tank in order to create a small vacuum.