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 Opener System
Used in 1974 models and some 1976-78 models, this system opens carburetor throttle a slight amount during deceleration. It maintains balanced air/fuel mixture and reduces hydrocarbon (HC) emissions. System consists of servo diaphragm (mounted on carburetor), vacuum control valve, and connecting tubes and hoses. See Figure. Servo diaphragm is adjustable and operates on vacuum from vacuum control valve.
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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