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 Valve
The cold start valve provides additional vaporized fuel during cranking mode to improve cold engine start-up. This circuit is required due to not enough fuel for cold engine start.
The starter solenoid supplied circuit is activated only during cranking mode. A thermal switch provides a valve ground path when engine coolant temperature is below 95°F (35°C).
Thermal switch consists of a bi-metallic material which opens at specified coolant temperature. This bi-metallic material is also heated by the thermal switch winding. This allows the valve to remain on for 8 seconds at -5°F (-20°C) coolant temperature.
The thermal switch closed time varies with coolant temperature. As coolant temperature rises, cold start valve operation time decreases.
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.