S-Type (X200) V8-4.0L (AJ28) (2001)
Fuel Temperature Sensor: Description and Operation
Engine fuel temperature (EFT) sensor
The EFT sensor, located on the fuel rail, is a thermistor which has a negative temperature coefficient (NTC). Fuel temperature is determined by the PCM
by the change in the sensor resistance. The PCM applies a 5 volts to the sensor and monitors the voltage across the pins to detect the varying resistance.
The PCM uses the EFT signal to adjust fuel pump pressure to prevent fuel vaporization and ensure adequate fuel supply to the injectors.