Fuel Rail Pressure Sensor
The fuel pressure in the rails is detected by the Fuel Rail Pressure (FRP) sensor which is located in the rear end of the bank two fuel rail.
The sensor measures the fuel pressure in the fuel rail which is supplied from the High Pressure (HP) fuel pump.
The FRP sensor is a piezo resistor type sensor. The sensor receives a 5V reference voltage supplied through a resistor within the Powertrain Control Module (PCM). The sensor produces an analogue signal of between 0 and 5V depending on the pressure sensed. Low Pressure (LP) gives a low voltage output and consequently HP gives a higher voltage output. The PCM uses this pressure signal to monitor the fuel pressure in the fuel rail and adjust the fuel metering valve to control the fuel pressure.
The PCM monitors the FRP sensor for faults and can store fault related Diagnostic Trouble Codes (DTC). These can be retrieved using an approved diagnostic system.
For additional information, refer to: FUEL CHARGING AND CONTROLS