EVAP Canister
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 Nissan Xterra, 2003 Nissan Sentra, 2003 Nissan Pathfinder, 2003 Nissan Murano, and 2003 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.
Remove EVAP canister. Plug vent hose and blow air into port "A". Air should flow freely out of port "B". See Fig 1. Replace EVAP canister, if operation is not as specified.