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.
Cold Start Spark Advance System: Operation
System provides manifold vacuum to distributor advance, through the DRVC and CSSA PVS, when engine coolant is below 128°F (53°C). When coolant temperature is between 128-235°F (53-113°C), vacuum reaches distributor from carburetor spark port through the cooling PVS, SDV, and CSSA PVS. When engine coolant is above 235°F (113°C), manifold vacuum is applied to distributor advance through SDV and CSSA PVS.
Use the Manual With the Right Hardware
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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.