Crankcase Ventilation Systems: Testing

The most accepted way to test the Ford truck PCV system is with PCV Tester C8AZ-6B627-A or equivalent. With engine at normal operating temperature, remove oil filler cap, hold tester over opening. Be sure there is no air leak between tester and rocker cover. If ball inside tester settles in green area system is operating properly. If tester ball settles in red area, the system is in need of repair.