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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Vacuum Switch: Description and Operation

Mounted on the driver's side firewall, this switch is activated when the throttle plate is closed, relaying this information to the ECU. The ECU uses this information to control the fuel delivery and secondary air management systems.