EVAP Canister Purge Valve
WARNING: This page does not describe the selected car, but rather 30 other vehicles, including the 2004 Mercury Sable, 2004 Mercury Mountaineer, 2004 Mercury Monterey, 2004 Mercury Marauder, and 2004 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.
The EVAP canister purge valve (Fig 1) is part of the Enhanced EVAP system that is controlled by the PCM. This valve controls the flow of vapors (purging) from the EVAP canister to the intake manifold during various engine operating modes. The EVAP canister purge valve is normally closed valve. The electronic EVAP canister purge valve (Fig 2) controls the flow of vapors electronically by way of a solenoid thereby, eliminating the need for an electronic vacuum regulator and vacuum diaphragm. The PCM outputs a signal between 0% and 100% duty cycle to control the EVAP canister purge valve. On applications with Electronic EVAP canister purge valve, the PCM outputs a signal between 0 mA and 1000 mA to control the solenoid.