Five Hundred AWD V6-3.0L VIN 1 (2005)
Fuel Pressure Sensor: Description and Operation
Fuel Rail Pressure Temperature (FRPT) Sensor
FUEL RAIL PRESSURE TEMPERATURE (FRPT) SENSOR
Fuel Rail Pressure Temperature (FRPT) Sensor
The FRPT sensor measures the pressure and temperature of the fuel in the fuel rail and sends these signals to the PCM. The sensor uses the intake
manifold vacuum as a reference to determine the pressure difference between the fuel rail and the intake manifold. The fuel return line to the fuel tank
has been deleted in this type of fuel system. The relationship between fuel pressure and fuel temperature is used to determine the possible presence of
fuel vapor in the fuel rail. Both pressure and temperature signals are used to control the speed of the fuel pump. The speed of the fuel pump sustains fuel
rail pressure which preserves fuel in its liquid state. The dynamic range of the fuel injectors increase because of the higher rail pressure, which allows the
injector pulse width to decrease.
