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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Air Injection Bypass Valve: Testing and Inspection


1. Disconnect air hose between air bypass valve and hose connector at air bypass valve.
2. Ensure all other hoses and connections are in good condition.
3. Start and run at idle.
4. Place finger over air bypass valve outlet and ensure air flows out.
5. Increase engine speed and quickly release accelerator, then ensure air stops flowing for a few seconds.
6. If air stops flowing for more than three seconds or does not flow out at all, replace air bypass valve.