2-Way Check Valve

On MPV, 2-way check valve is located on side of catch tank, near intake manifold. Remove check valve. Apply air pressure to port "B". See Fig 1 . Air should flow from port "C". Apply air pressure to port "C". Air should flow from port "A". Replace 2-way check valve as necessary.

Fig 1: Identifying Two-Way Check Valve

Courtesy of MAZDA MOTORS CORP.