2-Way Check Valve - Millenia, Protege & 626
WARNING: This page is about a different car, the 2001 Mazda Protege, 2001 Mazda Millenia, 2001 Mazda MX-5 Miata, 2001 Mazda MPV, and 2001 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.
Remove check valve, located at rear of vehicle by fuel filler. Using SST, apply +0.99 kPa of air pressure to port "A". See Fig 1 . Air should flow from port "B". Apply air pressure to port "C". Air should flow from port "A". If not as specified, replace 2-way check valve.