DTC P0087: Fuel Rail/System Pressure - Too Low: General Description
The ECM/PCM monitors the Fuel Pressure Regulator (FPR) using feedback (voltage) signal from the Fuel Rail Pressure Sensor (FRPS); based on the feedback (voltage) signal, the ECM/PCM can command the correct injector timing and pulse width for correct fuel delivery at all speeds and engine load conditions. The electric low fuel pressure pump supplies fuel to the mechanically driven high fuel pressure pump driven by the camshaft lobe. The FPR controls high fuel pressure from 40 bar (4 MPa/580.15 psi) to 150 bar (15 MPa/2175.57 psi). Under the abnormal condition of high pressure fuel system, the ECM/PCM goes into limp-home mode and fuel pressure is maintained the same as low pressure system.