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

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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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Cruise Control Vacuum Vent Solenoid: Testing and Inspection

1. Disconnect vacuum hose from the servo that leads to the dump valve.
2. Connect a hand vacuum pump to the hose, and draw vacuum. If vacuum cannot be obtained, the hose or dump valve is leaking, and should be replaced.
3. Step on brake pedal. The vacuum should be released. If not, adjust or replace the dump valve. 2.5 inches of Hg is minimum vacuum for normal servo operation. The vacuum source is a hose attached to a 5/16 inch engine vacuum fitting port on all except diesel. On diesel engines, the vacuum source is the vacuum reservoir VAC port.