Abstract: A fuel injection control device in which the amount of fuel injected by the fuel injector is increased at the time of acceleration. Namely, at the time of acceleration, the lean time and the rich time of the air-fuel mixture are calculated during the lean-rich discriminating time, which is basically equal to a time of an occurence of the lean time and the rich time when the air-fuel ratio is maintained at the stoichiometric air-fuel ratio at the time of acceleration. When the lean time becomes considerably longer than the rich time, the amount of fuel injected by the fuel injector is further increased.

Abstract: In an internal combustion engine, warming-up fuel enrichment is carried out in accordance with the temperature of the engine coolant. This fuel enrichment is further increased in accordance with the temperature of the engine coolant at the moment when a starter is turned on.

Abstract: Knocking in an engine is prevented from occurring by retarding an ignition timing. A basic ignition advance angle THB and a correction value THK for retardation of the ignition timing are computed in order that the ignition timing THF is calculated by using the formula THF=THB-THK. The knocking in the engine tends to take place, as the ignition timing advances. Determination is made as to whether the correction value THK is within a reference range AR. When such a determination is that the correction value THK is within the reference range, discrimination is made as to whether an octane number of the fuel to be supplied to the engine is less than a predetermined octane number of the fuel which is optimum for the engine. If the discriminated octane number of the fuel is less than the predetermined octane number, the ignition timing is retarded by 10 degree of a rotational angle of a crank shaft.

Abstract: An idling speed control device in an internal combustion engine comprising an idling speed control valve arranged in a bypass bypassing the throttle valve of the engine. The valve is fully opened at the start of the engine and closed to a controlled rate when the revolutional speed of the engine reaches a reference rotational value. At least two reference rotational values are provided depending upon a temperature; one of which is a higher value for the considerably high temperature, and the other is a low value for a normal temperature.

Abstract: An apparatus of controlling an air-fuel ratio for internal combustion engine, further comprising the steps of calculating a basic fuel injection duration based on an engine load and a rotational speed of the engine, obtaining a factor of air-fuel ratio feedback correction for allowing a fuel injection duration to perform a proportional-plus-integral action, based on an output of an oxygen sensor for detecting an residual oxygen concentration in an exhaust gas, calculating a mean value of said factor of air-fuel ratio feedback correction, varying a correction value by learning so that said mean value takes a value within a predetermined range centered at a predetermined value corresponding to a target air-fuel ratio, multiplying said mean value by said correction value, providing initial adjustment of load detection apparatus applied to said internal combustion engine for determining said basic fuel injection time duration in order to set said calculation result within said predetermined range, and obtaining t

Abstract: In a method for controlling a fuel injection amount of an internal combustion engine of the present invention, an incremental fuel amount is calculated in accordance with an engine running condition when a high load state of the engine is detected, and an upper limit value of the incremental fuel amount is gradually increased at predetermined intervals. When the incremental fuel amount is equal to or lower than the upper limit value, the fuel injection amount is increased to the extent of the incremental fuel amount. When the incremental fuel amount exceeds the upper limit value, the fuel injection amount is increased with the upper limit value. With this controlling method, the fuel consumption efficiency and acceleration response can be improved and the generation of knock in the engine can be suppressed during the period of the increase of the fuel injection amount in the high load state.

Abstract: A knocking in an engine is prevented from occurring by retarding an ignition timing. A basic ignition advance angle THB and a correction value THK for retardation of the ignition timing are computed in order that the ignition timing THF is calculated by using the following formula.THF=THB-THKThe knocking in the engine tends to take place, as the ignition timing advances. Determination is made as to whether the correction value THK is equal to a reference value or not and detection is made as to whether a rapid acceleration takes place. If the result of such determination is affirmative and no rapid acceleration is detected, discrimination is made as to whether an octane number of the fuel to be supplied to the engine is less than a predetermined octane number of the fuel which is optimum for the engine. When rapid acceleration is detected, the above-mentioned discrimination is not carried out so that the engine is controlled by the previous result of the discrimination of the fuel.

Abstract: In the control of an ignition timing retard limit in an internal combustion engine in which an ignition timing is sought from an intake air flowrate and an engine speed, and the ignition timing thus obtained is compared with the retard limit to prevent the ignition timing from being at the retard side beyond the retard limit, during detection of a rapid acceleration, the aforesaid retard limit is moved to the advance side to prevent the ignition timing from being over-retarded during the rapid acceleration.

Abstract: A method for regulating intake air flow for motor vehicle internal combustion engines in which the duty D of a signal for controlling the opening of an idle speed control valve (ISCV) is maintained at D=DG-b, as long as the car is still running in spite of the fact that deceleration operation or low speed running of the car is performed, where DG indicates the learning opening value of the ISCV in a bypass path, and b indicates a predetermined positive value to be corrected, thus strikingly improving so-called "driveability" and fuel consumption rate during the low speed steady running, without changing the ignition timing for the one set for the idling engine.

Abstract: An idle speed control valve is provided in a bypass path of an intake system and has its opening controlled by control pulse signals. The idle speed control valve is designed to increase the opening in proportion to the increase or decrease of the duty ratio of the control pulse signal and completely close the opening at 0% or 100% of the duty ratio. According to this invention, to completely close the idle speed control valve, instead of sending the control pulse signal of 0% or 100% of duty ratio to the idle speed control valve, the transmission of the control pulse signal is interrupted or the idle speed control valve is driven by continuous direct current.

Abstract: In an internal-combustion engine having a supercharger and an air-bypass passage for controlling the idle speed, when the engine is being cranked, the air-bypass passage is completely open. When the engine is not being cranked and the supercharger is operating, the air-bypass passage is completely closed. Further, when the engine is not being cranked and the supercharger is not operating, the opening of the air-bypass passage is adjusted in accordance with predetermined operating parameters.