Patent ID: 7210459

Claim:
A common-rail fuel injection system for leaking a portion of a high-pressure fuel to a low-pressure side, comprising: a common rail for storing the high-pressure fuel; an injector for injecting the fuel stored in the common rail; a control device for obtaining an injection quantity from the injector in accordance with an operating state so as to control an on-off valve of the injector based on the injection quantity; and a common-rail pressure sensor for detecting a common-rail pressure of the fuel stored in the common rail, wherein the control device includes correction means for obtaining a pressure drop quantity of the common rail pressure detected by the common-rail pressure sensor per unit time upon establishment of a predetermined learning condition, obtaining a leakage quantity change of the injector from the pressure drop quantity, and correcting the injection quantity injected from the injector for each injection based on the leakage quantity change, and wherein the correction means individually obtains the leakage quantity change of each of a plurality of injectors provided for an engine so as to individually correct the injection quantity from each of the injectors based on the leakage quantity change individually obtained for each of the injectors.