Quantity Control Valve
The quantity control valve regulates the rail pressure (high pressure control loop) together with the pressure regulating valve. ECM regulates the fuel quantity to be fed to the pump elements of the high pressure pump according to a PWM signal, according to the demand. Therefore, in comparison to an uncontrolled high pressure pump, the high fuel temperature (in the fuel return side) to be reduced. Through the reduction of the fuel quantity, which has to be compressed by the high pressure pump, the power consumption of the high pressure pump is also decreased.