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Coolant Sensors FAQ

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Courtesy of Sean Steinman and Peter Florance

It's time to play "Name that Sensor"! Thanks to Sean, here's a picture of the various coolant sensor and what their functions are.

Picture Label Bosch Sensor Name Function
Temp-Time Switch Thermal Time Switch Controls operation of cold start valve during cranking and limits to 8 seconds max to prevent flooding. Mating connector is brown
Temp Sensor for ECU Coolant Temp Sensor Provides Fuel Injection ECU with coolant temperature information for warm up fuel enrichment. Mating connector is amber or beige (to match sensor color)
Water Temp Sensor   Coolant temperature for dash temperature gauge
Bosch Connector   Typical Bosch fuel injection connector. Connector shown is for Thermal Time Switch

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