Positive Crankcase Ventilation: Testing and Inspection

Fig. 10 PCV valve flow rate chart:

Test the PCV valve for correct flow rate if the engine manifold vacuum is at least 14 in. Hg. When testing the vacuum, connect the gauge to a fitting as centrally located as possible on the intake manifold.
1. On four and six cylinder engines, remove valve from grommet in cylinder head cover.
2. On eight cylinder engines, remove valve from manifold vacuum source line.
3. Connect plastic hose of Tester J-23111 to valve, then start and run engine at idle. When performing this test, hold the PCV valve in a horizontal position and the tester in a vertical position. Lightly tap the valve to ensure an accurate reading.
4. If flow rate is not within specifications, Fig. 10, replace PCV valve.