900 L4-1985cc 2.0L DOHC Turbo EFI (1985)
Coolant Temperature Sensor/Switch (For Computer): Description and Operation
Temperature sensor (NTC resistor)
The temperature sensor is screwed into the inlet manifold flange. Its function is to provide the control module with information about the temperature
of the engine. The control module then regulates the quantity of fuel injected according to the temperature.
When starting from cold and during the first part of the warm-up period, the engine requires a much richer fuel-air mixture on account of the losses
due to condensation in the combustion chambers and intake pipe.
As the temperature of the engine rises, the quantity of fuel injected is decreased proportionately.
The temperature sensor consists of a brass body which holds a resistor of NTC type. NTC (Negative Temperature Coefficient) resistors have a low
resistance at high temperatures and a high resistance at low temperatures. The temperature sensor sends a continuous signal to the control module.
If the signal from the temperature sensor is interrupted, a signal will be simulated in the control module which gives a function on the assumption that
engine temperature is +20°C (68°F).
