I would like to know how I can verify what can be wrong with the evap system. How can I test that the sensor is working properly, how can I check that the valves are working correctly, and how do I know that the EVAP canister is working properly?
Remove and reinstall the gas cap, clear the code, and drive for a day and see if the codes come back.
Inspect the EVAP system for cuts/holes in tubes/hoses
Inspect for damaged or disconnected hoses around the Evap purge solenoid
Check and/or replace the sensor
Check and/or replace the purge valve