PCV Valve
- Operate engine at idle. Disconnect PCV valve with ventilation hose from cylinder valve cover. Plug PCV valve opening and verify vacuum is present. Remove PCV valve. Blow air through PCV valve port "A" and verify air flows from port "B". See Fig 1
.
- Blow air through PCV valve port "B" and verify that no air flows from port "A". Shake PCV valve and listen for rattle sound. Rattle sound should be present. If PCV valve operation is not as specified, replace PCV valve.
Courtesy of MAZDA MOTORS CORP.