Electronic Control of pressure common-rail fuel injection system of the Common Rail Road for the oil pressure in the fuel (or oil), depending on the common rail injection pressure fuel (or oil) pressure and control the power of electromagnetic valve time. Using high-speed electromagnetic valve fuel injection volume can be realized, the injection pressure, injection timing of flexible control and the inadequacies of the lies: electricity controlled manner difficult to achieve injection rate shape control and pre-spray, usually through mechanical control methods to achieve. Its typical representatives: (1) U.S. Caterpillar development of the HEUI of electronically controlled fuel injection system, using common rail, oil pressure in the fuel oil to drive the booster organizations. The largest injection pressure to reach 150MPa. (2) developed by the United States BKM Servojet of electronically controlled fuel injection system, using common rail, oil pressure in the fuel to drive the fuel booster organizations. The largest injection pressure over 150 MPa, Servojet of electronically controlled fuel injection system can be divided into SSI - 1 system and SSI - 2, difference is that: SSI - 1-pressure system with a nozzle, and SSI - 2 system is the traditional structure Nozzle.