Dashpot Control System

Engine must be at normal operating temperature. Ensure idle speed is correct.
Raise engine speed to 3000. Pinch vacuum hose between dashpot and Vacuum Transmitting Valve (VTV). See Fig 1 and Fig 2. Release throttle valve. Ensure dashpot is set and engine RPM is 2000. See Fig 3 and Fig 4.
To check VTV, run engine at 3000 RPM. Pinch vacuum hose between VTV and dashpot. Release throttle. Release pinched hose. Engine should return to idle within about one second. To check VTV off of vehicle, see Fig 5.

Fig 1: Testing Dashpot System (Non-Turbo)

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Fig 2: Testing Dashpot System (Supra Turbo)

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Fig 3: Adjusting Dashpot Idle Speed (Non-Turbo)

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Fig 4: Adjusting Dashpot Idle Speed (Turbo)

Fig 5: Testing Vacuum Transmitting Valve