Abstract: An air fuel ratio control apparatus, performs fuel decrease compensation during deceleration with respect to an air fuel ratio upon detection of a returning operation of a throttle valve. To avoid variations in torque which detract from a smooth ride, fuel decrease compensation is prohibited under the conditions that the opening of the throttle valve is in a full opening region and the amount of return movement of the throttle valve per unit time is equal to or less than a preset valve.

Abstract: An amount of fuel fed to an engine and determined by the rpm of the engine and a suction air flow rate is increased by a predetermined amount of fuel upon detection of acceleration. When the engine is suddenly accelerated from a low-speed operational region to enter a power zone, the above-mentioned predetermined amount of fuel is corrected based on the rpm of the engine and a quantity of change in the throttle valve opening degree.

Abstract: A fuel is injected based on the rpm of the engine and the suction air rate. The fuel injection amount is corrected depending on a map of fuel injection share correction coefficient prepared in advance and determined by data such as a throttle valve opening and the rpm of the engine so that amounts of fuel injected will be even at the respective cylinders. The fuel injection share correction coefficient is for correcting fuel deviation due to construction of suction passage to with the respective cylinders or for correcting fuel deviation due to arrangement of two injectors in one bore with respect to the throttle valve shaft.

Abstract: Disclosed is a fuel control apparatus in an internal combustion engine. When the running mode the engine is changed into acceleration again from deceleration after acceleration, the fuel becomes too rich if the conventional continuous correcting factor is used. In order to properly reduce the quantity of fuel supply in that case, the number of engine revolutions is counted from a point of initiation of deceleration to a point of initiation of acceleration again to thereby calculate a proper value of the continuous correcting factor corresponding to the count, so that fuel is supplied to the internal combustion engine with a quantity corrected by the thus calculated value of the continuous correcting factor.