Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Throttle Positioner
Connected to carburetor throttle lever, it prevents throttle from fully closing during deceleration. Diaphragm of throttle positioner is controlled by vacuum from the vacuum chamber of the coasting valve. When engine speed decreases to 1200±50 RPM, control box de-energizes coasting valve solenoid. This shuts off vacuum to throttle positioner diaphragm and allows carburetor throttle lever to return to normal idling position.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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