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 Modulator: Servicing
The decel valve calibration is preset at time of manufacture and normally does not require adjustment. To check and adjust, if necessary, proceed as follows:
With engine not running and curb idle speed previously set, position throttle lever against curb idle adjusting screw. Measure clearance between the throttle modulating diaphragm plunger and throttle lever. It should be 1/16". Adjust by loosening the jamnut and turning the diaphragm assembly.
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.