[3] Rail (1) Outline a. Stores pressurized fuel (0 to 150 MPa {0 to 1528.5 kg/cm 2 }) that has been delivered from the supply pump and distributes the fuel to each cylinder injector. A rail pressure sensor and a pressure limiter are adopted in the rail. b. The rail pressure sensor (Pc sensor) detects the fuel pressure in the rail and sends a signal to the engine ECU, the pressure limiter prevents the rail pressure from being abnormally high. This ensures optimum combustion and reduces combustion noise. Pressure Limiter Pressure Sensor Q000256E (2) Pressure Limiter a. The pressure limiter opens to release the pressure if an abnormally high pressure is generated. b.
When the rail pressure reaches approximately 200 MPa (2038 kg/cm 2 ), it trips the pressure limiter (the valve opens). When the pressure drops to approximately 50 MPa (509.5 kg/cm 2 ), the pressure limiter returns to its normal state (the valve closes) in order to maintain the proper pressure. Valve Open 200 MPa (2038 kg/cm 2 ) Valve Close 50 MPa (509.5 kg/cm 2 ) Q000257E Q000271E 16