Always start with the Powertrain On-Board Diagnostic (OBD) system check. This will reduce diagnostic time and prevent unnecessary parts replacement. The Enhanced Evaporative Emission (EVAP) control system diagnosis is covered in the following DTCs:

Important: Disconnect the hoses/pipes from the EVAP canister and the EVAP purge valve before applying compressed nitrogen.

Disconnect the vacuum source line at the purge valve and the manifold vacuum source. Remove the EVAP purge valve. Disconnect the purge line at the canister. Inspect all of the hoses/pipes/components for contamination. If a component is malfunctioning due to contamination, the component must be replaced. Contaminated of the hoses/pipes should be blown out with compressed nitrogen from the EVAP pressure/purge cart J 41413.

If carbon contamination of the system is evident, replace EVAP canister.

If the canister is cracked, damaged, or carbon contamination of the system is evident, replace the EVAP canister.