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Positive Crankcase Ventilation Valve: Service and Repair




PCV Valve Inspection

1) Disconnect PCV valve from cylinder head cover and install plug in head cover hole.
2) Run engine at idle speed.
3) Place your finger over end of PCV valve (1) to check for vacuum.

If there is no vacuum, check for clogged valve referring to step 4).





4) Stop engine and remove PCV valve (1).

Install clean hose to valve and check that there is air flow when blowing air into hose from [a] to [b] and that there is no air flow when blowing air into hose from [b] to [a] as shown in figure.

If faulty condition is found, replace PCV valve.





5) Remove head cover hole plug.
6) Tighten PCV valve to specified torque. Cylinder Head Cover Removal and Installation