Carbon Canister

Remove hose from valve port. Blow through hose. Air should pass through purge and vent lines, but should not pass through vacuum lines. See Fig 2 .

Fig 1: Testing Fuel Vapor Vent Line

Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 2: Testing Canister Purge

Courtesy of NISSAN MOTOR CO., U.S.A.