Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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PCV Valve Hose: Testing and Inspection

PCV valve and ventilation hose
1. Warm up engine to normal operating temperature and run engine at idle.
2. Remove PCV valve from cylinder head cover by pulling ventilation hose.




3. Block PCV opening.
4. Verify that vacuum is felt.
5. Remove PCV valve from ventilation hose.
6. Blow low pressure air through larger diameter inlet. Air should pass through valve.
7. Blow low pressure air through smaller inlet of PCV valve. Air should not pass through valve.
8. Replace PCV valve if PCV valve fails any of these tests.