DIESEL ENGINE FUEL INJECTION CONTROL DEVICE

摘要

PROBLEM TO BE SOLVED: To reduce soot emission at a time of a high load in a diesel engine equipped with a low-pressure EGR system.SOLUTION: A controller (control unit 100) actuates a low-pressure EGR system 52 and controls a fuel injection valve (injector 21) to perform post injection after main injection if an operating state of an engine body 10 is in a predetermined high load range in which a turbocharger (turbo charger system 6) performs turbocharging. The controller exerts a post-injection switching control to set an injection quantity of the post injection to a first injection quantity and set injection timing of the post injection to first timing in a low load range equal to or lower than a predetermined load, and to set the injection quantity of the post injection to a second injection quantity smaller than the first injection quantity and set the injection timing of the post injection to second injection advanced over the first injection in a high load range exceeding the predetermined load.