A code P0440 could mean one or more of the following has happened:

The gas cap is not installed or working properly
The purge solenoid has failed
The canister is plugged and not working properly
Possible SolutionsWith a P0440 OBD-II trouble code, diagnosis can be tricky at times. Here are some things to try:

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
Have a professional use a smoke machine to detect leaks

Answered by rasmataz
68 questions asked

Thanks for the feedback...I will do the gas cap deal today...but if that doesn't work how do I find all those other things you talked about...

Response from khubbard5
1 question asked