I have a 2001 Sentra GXE. 1.8l. Two check engine codes. PO455.And P1448.Help

What is your question?

I know that the first one is Evap system Leak indicating Maybe a bad evap canister valve. Or bad gas cap. Gas cap looks fine. The other is "NO DTC definition found. I don't know what that means. The strange thing is that the car dies a lot when coming to a stop when the engine decelerates. It starts right back up every time. No problem. I take it out of gear, come to a stop and it dies right around idle like clock work. Any ideas? I wouldn't think a faulty evap canister valve would cause this.