I've got a code P1457 on my 2003 Civic. Have seen many posts and videos referencing the EVAP Canister Shut Valve as the culprit:

http://forums.clubrsx.com/showthread.php?t=771294


This guy here fixed his because it wasn't sealed:
I blew on mine to check for air leaks, and it didn't seem to have any.

Also did this test with a 9V battery to see whether the valve was working, and it is.
My valve does look rusted to hell, but my tests indicate it's still working fine.
Any suggestions on where to go next?

If there's anything else I can try before driging it to the shop for a diagnosis, I will.

Thanks