B350 1 Ton Van V8-5.9L VIN Z (1992)
Coolant Temperature Sensor/Switch (For Computer): Description and Operation
LOCATION
The sensor is located near the thermostat housing.
OPERATION
The engine controller receives information regarding engine operating temperature from the coolant temperature sensor. Engine coolant
temperature is the same as engine operating temperature.
The sensor is a variable resistor. As coolant temperature varies, the coolant temperature sensors resistance changes. This results in a different input
voltage to the engine controller.
The engine controller contains different spark advance curves for different engine operating conditions. There are unique spark advance schedules
for cold and warm engine operation that have been added to reduce engine emission and improve driveability. The engine controller will supply
slightly richer air-fuel mixtures and higher idle speeds until normal operating temperatures are reached.
All spark advance testing should be done with the engine fully warmed.
