EVAP Leak Detection System Components

• Service Port:  Used with special tools like the Miller Evaporative Emissions Leak Detector (EELD) to test for leaks in the system.
• EVAP Purge Solenoid:  The PCM uses the EVAP purge solenoid to control purging of excess fuel vapors stored in the EVAP canister. It remains closed during leak testing to prevent loss of pressure.
• EVAP Canister:  The EVAP canister stores fuel vapors from the fuel tank for purging.
• EVAP Purge Orifice:  Limits purge volume.
• EVAP System Air Filter:  Provides air to the LDP for pressurizing the system. It filters out dirt while allowing a vent to atmosphere for the EVAP system.

Fig 1: Identifying EVAP Leak Detection System Components

Courtesy of DAIMLERCHRYSLER CORPORATION