Refueling Control Valve Test (Altima)
Remove refueling control valve from fuel tank. See VACUUM DIAGRAMS article for location. Inspect control valve for cracks. Blow air into port "A". Air should flow freely out of port "B". See Fig 1. Blow air into port "C". Air should not flow. Apply 2.9 psi (20.00 kPa) of pressure to ports "A" and "C". Air should not escape from port "B". If operation is not as specified, replace control valve. If operation is as specified, test is complete.