Diagnostic Aids

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Inspect for a loose, missing, damaged, or incorrect fuel fill cap.
Inspect for a damaged fuel filler neck seal surface.
A blockage or restriction in the EVAP purge solenoid valve, purge pipe, EVAP canister, or vapor pipe, can cause this DTC to set.
The EVAP system can be filled with smoke more quickly and completely by opening the system opposite the end where the smoke is injected. For example, when injecting smoke at the service port remove the fuel fill cap, or temporarily leave the vent open, until smoke is observed, then close the system and continue testing. If using a fuel cap adapter at the filler neck, use the GE 41413-VLV EVAP Service Port Vent Fitting at the service port to allow the system to fill faster.
To help locate intermittent leaks using the GE 41413-A Evaporative Emissions System Tester (EEST), move all EVAP components while observing smoke with the GE 41413-SPT High Intensity White Light.
Individual components can be isolated and tested using adapters in the J 41413-300 EVAP Cap and Plug Kit.
A condition may exist where a leak in the EVAP system only exists under a vacuum condition. This type of leak may be detected by using the scan tool Purge/Seal function to create a vacuum in the EVAP system and then observe the FTP parameter for vacuum decay.