Fuel injection control device for diesel engine

Abstract

A fuel injection control device suited to use in automotive diesel engines. The device comprises sensors for producing signals upon sensing various states of operation of the engine, including a temperature sensor adapted to produce a temperature signal upon sensing the temperature of a coolant for cooling the engine, a first arithmetic operation means for determining the rate of fuel injection in accordance with the signals delivered by the sensors, and a second arithmetic operation means for determining the timing of fuel injection in accordance with the signals delivered by the sensors. The control device further comprises a first temperature judging means for comparing the coolant temperature signal with a predetermined reference temperature to judge whether the coolant temperature exceeds the reference temperature, an fuel injection rate corrrecting menas for effecting a subtractive correction of the fuel injection rate determined by the first arithmetic operation means, and a timing correcting means for advancing the fuel injection timing determined by the second arithmetic operation means. When the coolant temperature exceeds the reference temperature, the fuel injection rate correcting means and the injection timing correction means operate to decrease the fuel injection rate and to advance the fuel injection timing, respectively.