Crown Victoria V8-4.6L VIN W (2000)
Fuel Temperature Sensor: Description and Operation
Engine Fuel Temperature Sensor
The Engine Fuel Temperature (EFT) sensor is a thermistor device in which resistance changes with temperature. The electrical resistance of a
thermistor decreases as temperature increases, and increases as temperature decreases. The varying resistance affects the voltage drop across the
sensor terminals and provides electrical signals to the PCM corresponding to temperature.
Thermistor-type sensors are considered passive sensors. A passive sensor is connected to a voltage divider network so that varying the resistance of
the passive sensor causes a variation in total current flow.
Voltage that is dropped across a fixed resistor in series with the sensor resistor determines the voltage signal at the PCM. This voltage signal is equal
to the reference voltage minus the voltage drop across the fixed resistor.
Engine Fuel Temperature (EFT) Sensor
The EFT sensor measures the temperature of the fuel near the fuel injectors. This signal is used by the PCM to adjust the fuel injector pulse width and
meter fuel to each engine combustion cylinder.
