| 摘要 |
PROBLEM TO BE SOLVED: To prevent production of noise and deterioration of exhaust emission by stopping the feedback control of sub-injection, when the target sub-injection amount in sub-injection is smaller than the minimum fuel injection amount detected according to common rail pressure. SOLUTION: In a system, where fuel injection is divided into main injection and sub-injection preceding the main injection or delayed from it according to the detection signal from a detecting means for detecting fuel injection from an injector 1 provided on every cylinder, a target sub-injection amount Qt obtained according to the engine operating conditions and a preset value Q1 of fuel injection amount obtained corresponding to a pressure Pr of a common rail 2 detected by a pressure sensor 3 immediately before the start of sub- injection are compared by a controller 12. When Qt<Q1, feedback control of sub-injection is stopped to cause open-loop control to be conducted, for example. Thus, combustion can be kept from being unstable. |
