Abstract: An exhaust gas recirculation control system for bringing an actual amount of air that is detected by an air flow sensor to a target value by feedback controlling a valve lift of an EGR valve throttles down a throttle valve immediately before an exhaust gas inlet port of an intake passage when a large amount of exhaust gas is intended to be recirculated. When the largest actual amount of air is reduced due to closing the throttle valve, the target amount of air is changed smaller so as to ensure the actual amount of air to reach the target value through the feedback control.

Abstract: A fuel control apparatus of an engine comprises fuel control means for controlling fuel supply means in such a manner that an amount of fuel supplied to the engine corresponds to an intake pressure on the basis of a signal outputted from intake pressure detecting means for detecting the intake pressure of an intake passageway, exhaust resistance changing means for changing an exhaust resistance of an exhaust passageway correspondingly to the operating condition of the engine, and correction means for correcting a supply amount of the fuel to be controlled by the fuel control means when the exhaust resistance of the exhaust passageway is changed by the exhaust resistance changing means.

Abstract: In an automotive power plant including a combustion engine, intake and exhaust passages communicated with a combustion chamber for an introduction of an air-fuel mixture into and a discharge of exhaust gases from the combustion chamber, respectively, a fuel injector for injecting a controlled amount of fuel into the combustion chamber together with air sucked through the intake passage, and a throttle valve of which opening is adjustable for controlling the flow of the air through the intake passage, a fuel control system for determining the amount of fuel to be injected into the combustion chamber in dependence on the amount of air being sucked.

Abstract: A fuel control apparatus of an engine comprises fuel control means for controlling fuel supply means so that an amount of fuel supplied to the engine corresponds to an intake pressure on the basis of a signal outputted from intake pressure detecting means for detecting the intake pressure of an intake passageway, intake resistance changing means for changing a resistance of the intake air flowing through the intake passageway correspondingly to the operating condition of the engine, and correction means for correcting a supply amount of the fuel to be controlled by the fuel control means when the resistance of the intake air flowing through the intake passageway is changed by the intake resistance changing means.