My daughter has had this issue for a year now.
She has a PO440 CODE, Minor leak.
Teh gas cap has been replaced, The Vent Solenoid (The one on the rear Crossmember) has been disassembled and cleaned. with Voltage added, it holds as I try and blow through it.
Looking at an issue I have with a Vacuum line attached to the Purge Solenoid ( On intake manifold, passenger side, rear)

Is there a rubber 'o' ring in the hose that attaches to the Purge solenoid that keeps it from leaking when the hose is snapped in? My little plastic snap ring on the hose is broken, will that cause this Code?
BTW NAPA only shows a Vent solenoid for my '99 but they call it the Purge solenoid.

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There is a seal in the line and having a bad clip won't help, but are you leaking at that point? If you have replaced the usual components and still not cured the condition, you may want to consider having it properly diagnosed. This involves a smoke machine pushing fake smoke into the system and looking for said smoke coming out of various different places in the EVAP system. At this point, any line, fitting, etc could be the culprit.

 

I had the fuel pump replaced drove for about 80 miles , the ses light came on, same code.

 

If that is the case, they likely broke a fitting on the tank. The front fitting on the tank can break quite readily. This has been covered in other threads with pictures and part numbers. If you can't find them via the search function or need further information, you may want to consider creating your own thread.