Abstract: Air-fuel ratio control of an internal combustion engine is performed using sensors for detecting operating conditions of the engine, such as the intake air amount, engine rotational speed, or air-fuel ratio; a fuel injection valve driven by an electrical signal to inject fuel; and a control circuit for receiving signals from the operating condition sensors, performing predetermined operations and generating an electrical signal for driving the fuel injection valve. The control circuit performs a step of calculating an air-fuel ratio variation D(A/F) with respect to an optimum air-fuel ratio based on the ratio of a change .DELTA.F, of an air-fuel ratio correction signal F during acceleration under air-fuel ratio feedback control based on a signal from the air-fuel ratio sensor, to an acceleration amount A, and a step of controlling a transient fuel correction ratio f(AEW) based on the obtained air-fuel ratio variation D(A/F).

Abstract: A method for controlling an engine includes the steps of sampling instantaneous flow rates of intake air supplied to the engine, computing the quantity of intake air to be supplied to the engine in an intake stroke on the basis of the sampled instantaneous intake air flow rates, computing the quantity of injected fuel in the intake stroke on the basis of the computed intake air quantity, and injecting the computed quantity of fuel to the engine. In the method, the step of computing the injected fuel quantity includes the step of computing the ratio between the instantaneous intake air flow rate sampled at a reference timing in the preceding intake stroke and that sampled at reference timing in the present intake stroke for correcting the quantity of intake air supplied in the present intake stroke.

Abstract: A feedback air-fuel ratio control system for an internal combustion engine has an O.sub.2 -sensor for detecting the concentration of oxygen in exhaust gases of the engine, a coolant temperature sensor, and a circuit for disabling the feedback control operation at a low coolant temperature during warming-up of the engine. The feedback control system is also disabled when the engine is rapidly accelerated or decelerated, even if the engine is warming-up at coolant temperatures greater than the low coolant temperature state.

Abstract: A method for controlling the air-fuel ratio in an internal combustion engine in which the correction value of a transient fuel injection amount is decided, at a predetermined interval, in accordance with the acceleration or deceleration state of the engine, and the amount of fuel injection supplied to the engine is corrected by the decided correction value. In the process of the correction, the deviation of the air-fuel ratio from a reference air-fuel ratio in acceleration or deceleration of the engine is detected, and the correction value of the fuel injection amount correction in the transient state of the engine in accordance with the detected air-fuel ratio deviation is determined. In the correction of amount of fuel injection in the transient state of the engine, the correction value is decided on the basis of a factor for deciding the correction value and the blunted value of the factor for deciding the correction value.

Abstract: Synchronous fuel injection amount of injected from a fuel injector in synchronization with rotation of an engine is controlled in relation to the second time differential of either the intake pipe pressure or intake flow rate.

Abstract: A method for controlling the quatity of fuel being supplied to an internal combustion engine, immediately after termination of a fuel cut operation which is carried out when the engine is operating in a predetermined operating region while it is decelerating. The fuel quantity is controlled to a required value after termination of a fuel cut operation, by increasing a quantity of fuel set at least as a function of intake pipe pressure by an increment which is set in synchronism with generation of pulses of a predetermined control signal. The increase of the fuel quantity is effected for a period of time after a transition of the operative state of the engine from the fuel cut operation to a normal operation wherein fuel supply is effected has been detected and before a predetermined number of pulses of the above control signal are generated, so long as the magnitude of a variation or change in the rotational speed of the engine is determined to be larger than a predetermined value.

Abstract: A method of controlling the supply of fuel to an internal combustion engine, wherein the value of at least one operating parameter of the engine is detected in synchronism with generation of pulses of a control signal generated at predetermined crank angle positions of the engine, and fuel is supplied to the engine in a quantity responsive to the detected value of the at least one operating parameter.

Abstract: An electronically controlled fuel injection apparatus for internal combustion engine which increases the rate of fuel injection when the engine speed drops by a rate more than a predetermined rate under a condition that the aperture of the throttle valve is minimum, that is, under an idling condition. In order to increase the rate of fuel injection, the width of the basic fuel injection pulse is enlarged which is given according to the engine speed and the intake air flow rate, or, in addition to the basic fuel injection pulse, a predetermined rate of fuel is injected asynchronously, i.e., independently from the crank angle of the engine.

Abstract: For an internal combustion engine workable at a variable speed, a fuel supply adjusting system makes a fuel supplying device supply fuel to the engine on acceleration thereof. A commanded engine speed is successively detected at a first, a second, and a current instant of time. Judgment is made in response to the commanded engine speeds at the first and the current instants whether or not the engine is being accelerated. A rate of the acceleration is calculated in response to the commanded engine speeds at the second and the current instants. An additional amount of supply of the fuel is decided by the fuel supply adjusting system in response to the rate of the acceleration and to an actual engine speed only when the engine is being accelerated.

Abstract: A method of detecting the opening of a throttle valve in a fully closed position in an internal combustion engine. A first predetermined opening value larger than the minimum opening value of the throttle value determined by structural factors is stored as an initial value of a fully closed position-discriminating variable, while a second predetermined opening value smaller than the minimum opening value is stored as an initial value of a stored opening value of the throttle valve in the fully closed position detected by a throttle valve opening sensor. The fully closed position-discriminating variable is updated or set to a newly detected throttle valve opening value when the latter is smaller than the former.

Abstract: A method of controlling the air-fuel ratio of an air-fuel mixture being supplied to an internal combustion engine by the use of a coefficient which is variable in value in response to the output of an exhaust gas ingredient concentration detecting means, while the engine is operating in a predetermined air-fuel ratio feedback control region. When the engine is operating in the above region, a calculation is made of a mean value of values of the coefficient which have been applied in the past feedback control. When a transition occurs in the engine operation from a region other than the predetermined feedback control region to the latter region, the calculated mean value of the coefficient is corrected by a predetermined value through multiplication or addition, and the air-fuel ratio feedback control is initiated by the use of the corrected mean value of the coefficient as an initial value.

Abstract: A fuel injection control apparatus for use of an engine. The apparatus varies a minimum amount of fuel to be injected into the engine according to such conditions as the engine speed increases or decreases. When the engine speed increases, a first minimum amount of fuel is set in low and intermediate engine speed zones and the first minimum amount is converted to a second minimum amount of fuel which is less than the first minimum amount in a high engine speed zone. Contrary to this, when the engine speed decreases, the second minimum amount of fuel is set in high and intermediate engine speed zones, and the second minimum amount of fuel is converted into the first minimum amount of fuel in the low engine speed zone. Thus, according to the increase or decrease in an engine speed, a minimum amount of fuel is varied with a hysteresis.

Abstract: A process whereby fuel injection is interrupted in response to detection of a deceleration and injection is again ordered when a threshold linked to the engine speed is reached. The engine speed (N) or period of rotation (T) is measured from consecutive equal intervals or angles of rotation. A difference (.DELTA.T, .DELTA.N) is then computed between the value of the last measured speed or period and the value seen through a high-pass filter of the speed or period measured at the preceding interval. This difference (.DELTA.T, .DELTA.N) is compared with a fixed threshold (S) and if an engine deceleration condition is detected, fuel injection is again ordered when the difference (.DELTA.T, .DELTA.N) is greater than the threshold (S).

Abstract: The minimum fuel injection time is on electronically controlled fuel injection engine is set in relation to the running condition of the engine. For example, in shift change, when the throttle valve is in the idling angle and the revolution speed of the engine is high, the minimum fuel injection time is set to a small value to improve the efficiency of fuel consumption. Also, at the completion of fuel cut-off when the revolution speed of the engine is low, the minimum fuel injection time is set to a large value to improve the driveability of the vehicle.

Abstract: A method and an apparatus for overrunning control in an internal combustion engine are proposed, which operate with an overrunning cutoff and the reestablishment rpm of which is dependent on rpm and on time. At the onset of overrunning, a higher reestablishment rpm is selected, and once the rpm falls below a predetermined rpm value the reestablishment rpm is reduced according to a time function to a lower threshold value. The method may be realized by a controlled system, as well as by a control apparatus operating with analog circuitry.

Abstract: A control method of supplying an internal combustion engine with required quantities of fuel appropriate to operating conditions of the engine, in synchronism with pulses of a control signal generated at predetermined crank angle positions of the engine. When the engine is operating in a predetermined accelerating condition, a correction variable for increasing the fuel supply quantity for supply to the engine at acceleration is determined as a function of the number of pulses of the above control signal generated after the predetermined accelerating condition has been detected for the first time, as well as of the rate of change of the value of a predetermined operating parameter indicative of the engine load which is detected in synchronism with a predetermined sampling signal, to thereby set a quantity of fuel for supply to the engine at acceleration.

Abstract: A fuel controller has a fuel cut-off device in the form of a solenoid valve connected to an intermediate part of an air bleed commmunicating with the well of a variable choke carburetor. The fuel controller also employs a vacuum changeover valve which communicates with the engine intake manifold through a passage way and is connected to the air bleed between the solenoid valve and an air jet upstream of the solenoid valve. The solenoid valve is opened when the engine is decelerating in order to allow the well and the air bleed to communicate with each other, thereby controlling the air-fuel ratio. When the key switch is IC, the air bleed and the vacuum changeover valve communicate with the well, thereby cutting the supply of fuel to the mixing chamber.

Abstract: The invention is directed to a current regulator for an electromagnetic load used in conjunction with an internal combustion engine. The regulator produces positive and/or negative currents flowing through an electromagnetic load. In this arrangement, the two potentials present at a precision resistor that is connected in series with the load are adjusted to freely selectable values. To obtain both positive and negative currents, the current defined by the voltage drop occurring along the precision resistor is provided by a bridge circuit made up of four current-controlling arrangements. Allowance can be made for particular operating conditions of the current regulator simply by presetting desired values.

Abstract: A fuel injection device of a diesel engine which stops fuel injection and throttles intake air during engine braking so that engine vibration, noise, harmful exhaust gas, and fuel consumption are all reduced. The device includes an intake valve interlocked with an accelerator to throttle intake air during accelerator nonoperation, sensors for detecting an engine braking condition, and a computer for controlling fuel injection in response to signals from engine sensors.

Abstract: A fuel cut-supply control system for a multiple-cylinder internal combustion engine which can effectively prevent engine vibration or shock generated when fuel is cut off or resupplied. The cylinders of the engine are divided into two cylinder groups and fuel is cut off or resupplied to one cylinder group a predetermined delay time after fuel has been cut off from or resupplied to the other cylinder group. The delay time is so determined that vibration caused by the first cylinder group is 180 degrees out of phase with that caused by the second cylinder group. The control system according to the present invention comprises a delay circuit and a first and second fuel cut-supply control sections, in addition to the conventional fuel cut-supply control system.

Abstract: A control device having certain criteria which must be fulfilled in order to trigger an acceleration enrichment. Criteria are a defined number of successive load values of increasing tendency and/or an actual load value with a defined distance above the arithmetic mean of a number of preceding load values. For the acceleration enrichment itself operational parameters, such as rpm, load, load gradient, temperature and number of revolutions since the triggering of the acceleration are processed.

Abstract: A control device for a supercharged internal combustion engine is proposed, in which a device for fuel limitation during overrunning is also used for limiting the fuel metering in a definite manner in the event that a threshold value of the charge pressure is exceeded. To this end, a switch actuated by the charge pressure is connected parallel to a switch triggered during overrunning. In the event that the threshold value of the charge pressure is exceeded, overrunning is simulated accordingly, and the associated provisions for fuel limitation for such an event are initiated.

Abstract: A method for controlling the quantity of fuel being supplied to an internal combustion engine having a power transmission means for transmitting engine torque to vehicle wheels. The fuel quantity is controlled to a required value after termination of a fuel cut operation which is effected at deceleration of the engine, by increasing a quantity of fuel set at least as a function of intake pipe pressure by an increment which is set in synchronism with generation of pulses of a predetermined control signal. The increase of the fuel quantity is effected for a period of time after a transition of the operative state of the engine from the fuel cut operation to a normal operation wherein fuel supply is effected has been detected and before a predetermined number of pulses of the above control signal generated are generated, so long as the power transmission means remains in a disengaged state. Preferably, the above increase of the fuel quantity is effected only when the engine speed is lower than predetermined rpm.

Abstract: A method for electronically controlling a fuel injection device which injects fuel into an internal combustion engine, so as to supply a required quantity of fuel to the engine when it is accelerating. It is determined whether or not the engine is operating in a predetermined accelerating condition or in a predetermined decelerating condition, in synchronism with generation of pulses of a control signal having a constant pulse repetition period and being independent of rotation of the engine. When the engine is determined to be in the predetermined accelerating condition, fuel injections are consecutively effected a predetermined number of times in synchronism with generation of pulses of the above control pulse. The above consecutive fuel injections are continued until the above predetermined number of times are reached, so long as the engine is determined not to be in the above predetermined decelerating condition.

Abstract: A fuel injection quantity is calculated on the basis of an engine speed and an engine load and is corrected by an output incremental value determined in accordance with acceleration and deceleration of an engine, at least. The position of an intake throttle valve is detected with regard to whether it is located within a small-opening region, an intermediate-opening region or a large-opening region. When the intake throttle valve is switched over from the small-opening region to the large-opening region, the output incremental value is increased to its maximum value. When the intake throttle valve is switched over from the small-opening region to the intermediate-opening region, the output incremental value is increased such as to gradually approach the maximum value. When the intake throttle valve is switched over from the large-opening region to the small-opening region, the output incremental value is decreased to almost zero.

Abstract: A fuel supply control method for controlling the fuel supply to an internal combustion engine at deceleration, wherein the valve opening of a throttle valve of the engine is detected while the throttle valve is being closed and each time each pulse of a predetermined sampling signal is generated, a variation in the same valve opening occurring between adjacent pulses of the sampling signal is determined as a control parameter value, and the quantity of fuel being supplied to the engine is reduced by an amount corresponding to the control parameter value.

Abstract: A method of sequentially injecting fuel into the cylinders of a multi cylinder internal combustion engine in predetermined sequence in synchronism with generation of pulses of a trigger signal, wherein the quantity of fuel to be injected into each cylinder is set to a value appropriate to an operating condition of the engine then detected, upon generation of each pulse of the same signal, and the fuel supply to each cylinder is interrupted when the engine is decelerating in a predetermined operating condition. When it is determined that a predetermined condition for terminating the interruption of the fuel supply to the engine is satisfied, one of the above sequential injections is effected into a cylinder corresponding to a present pulse of the trigger signal at the time of generation of a present pulse of the same signal, and simultaneously an additional injection is effected into another cylinder corresponding to a preceding pulse of the trigger signal.

Abstract: An engine wherein a basic fuel injection flow rate from an injector is obtained based on an intake manifold pressure and an engine rotational speed. A change with time of the opening degree of a throttle valve and a change with time of the intake manifold pressure are calculated, and the basic fuel injection flow rate is corrected commensurate with the values of the changes described above to cause the basic fuel injection flow rate to be an ideal air-fuel ratio. When the change with time in opening degree of the throttle valve or the change with time of the intake manifold pressure is smaller than the respective predetermined values, the basic fuel injection flow rate is corrected, and, after the correction, if the values of changes thereof become smaller than the respective predetermined values, the basic fuel injection flow rate thus corrected is caused to approach the injection flow rate before the correction.

Abstract: An electronic fuel injection control includes a main fuel control circuit, a transient enrichment control circuit temporarily increasing fuel flow as a result of increasing of a demand signal, and temperature compensation means non-linearly varying the effect of the enrichment control with engine temperature. The temperature compensation means preferably includes a temperature "window" detector which acts to increase the effect of the enrichment control whenever the engine temperature is between prescribed limits.

Abstract: A method of controlling the fuel supply to an internal combustion engine immediately after termination of a fuel cut operation thereof which is effected at deceleration of the engine, in a manner increasing the quantity of fuel being supplied to the engine by an increment which is set in sychronism with generation of pulses of a predetermined control signal generated at predetermined crank angle positions of the engine. The magnitude of change of the rotational speed of the engine is detected for a period of time after a transition of the operative state of the engine from the fuel cut operation to a normal operation wherein fuel supply is effected has been detected and before a predetermined number of pulses of the above predetermined control signal are generated.

Abstract: A vehicle including an internal combustion engine having a fuel supply system for providing a supply of fuel, a deceleration detecting device for detecting that the engine is in deceleration, a heater having heat exchanger for bringing air in the vehicle into a heat exchange relationship with engine cooling medium so that the air in the vehicle is heated by the engine cooling medium, a heater operation detecting device for detecting that the heater is in operation, a fuel supply control device responsive to outputs of the deceleration detecting device and the heater operation detecting device for interrupting the supply of fuel when the engine is in deceleration and the heater is not in operation.

Abstract: A method for controlling the quantity of fuel being supplied to an internal combustion engine, immediately after termination of a fuel cut operation which is carried out when the engine is operating in a predetermined operating region while it is decelerating. The fuel quantity is controlled to a required value after termination of a fuel cut operation, by increasing a quantity of fuel set at least as a function of intake pipe pressure by an increment which is set in synchronism with generation of pulses of a predetermined control signal. The increase of the fuel quantity is effected for a period of time after a transition of the operative state of the engine from the fuel cut operation to a normal operation wherein fuel supply is effected has been detected and before a predetermined number of pulses of the above control signal are generated, so long as the magnitude of a variation or change in the rotational speed of the engine is determined to be larger than a predetermined value.

Abstract: Fuel is injected in synchronism with the crank angle. In addition, an engine acceleration state is detected from the second-order differential value of the intake-pipe pressure, and the quantity of the asynchronous fuel injection in which fuel is injected in asynchronism with the crank angle is increased in an early stage of acceleration but is decreased after the early stage of acceleration. Moreover, no asynchronous injection is carried out in a low engine speed region. It is thereby possible to obtain an optimum air-fuel ratio in accordance with the engine acceleration state.

Abstract: A method for controlling the quantity of fuel being supplied to an internal combustion engine having a power transmission means for transmitting engine torque to vehicle wheels. The fuel quantity is controlled to required values after termination of a fuel cut operation which is effected at deceleration of the engine, by the use of increments set in synchronism with generation of pulses of a predetermined control signal. The state of engagement of the power transmission means is detected for a period of time after a transition of the operative state of the engine from the fuel cut operation to a normal operation wherein fuel supply is effected has been detected and before a predetermined number of pulses of the above predetermined control signal are generated.

Abstract: An ignition timing controlling system of an engine for controlling a fuel injection flow rate and the ignition timing on the basis of intake air flow rate and an engine rotational speed. The system controls the ignition timing to the maximum ignition advance angle when a throttle valve is fully closed and the fuel injection is stopped as in the course of deceleration, or the throttle valve is fully closed and the fuel injection is stopped after a predetermined times of ignition have been effected, and controls the ignition timing to the optimum ignition advance angle when, thereafter, the fuel injection has returned.

Abstract: A method for controlling a control system which controls an internal combustion engine, in response to at least one control parameter including intake pipe pressure, immediately after termination of a fuel cut operation. When a transition is detected from an operating condition of the engine requiring interruption of fuel supply to the engine to an operating condition of the engine requiring fuel supply to the engine, a value of the intake pipe pressure detected by pressure sensor means is changed by a predetermined amount, from a time immediately after the above transition has been detected to a time the engine finishes a predetermined number of strokes after the transition, and the value of the intake pipe pressure thus changed is applied for controlling the above engine control system.

Abstract: A method of controlling the fuel supply to an internal combustion engine at deceleration thereof, wherein the fuel supply to the engine is interrupted when the engine is operating in a predetermined operating region in which is satisfied at least a condition that the intake passage pressure is lower than a predetermined value, while the engine is decelerating. The predetermined value of intake passage pressure is corrected in a manner responsive to a detected value of atmospheric pressure encompassing the engine. Preferably, the intake passage pressure is detected in terms of absolute pressure at a zone downstream of a throttle valve arranged therein, and the above predetermined value of intake passage pressure is corrected to smaller values as the detected value of the atmospheric pressure decreases.

Abstract: A current regulator is proposed for use in an electronically controlled, continuously operating gasoline injection system, with the aid of which a control element can be supplied with different current values depending upon the operating states of the engine. In addition to a current regulating phase during active operation, it is possible with the proposed current regulator to reverse the direction of current flow in the control element for the sake of blocking the supply of fuel during overrunning. Towards this end a circuit apparatus links signals relating to rpm, throttle valve position and temperature. Furthermore two safety circuit arrangements are proposed for the current regulator, so that in case of a failure of important components there is no impairment of safety, and emergency operation is assured.

Abstract: A fuel supply control method for controlling the fuel supply to an internal combustion engine at deceleration, wherein the fuel supply to the engine is interrupted when the engine is operating in a predetermined operating region while it is decelerating. The fuel supply is interrupted when the engine is operating in either of the following operating conditions: (1) when the throttle valve is in a substantially fully closed position while the engine is decelerating; and (2) when the throttle valve is in a position other than the substantially fully closed position and simultaneously the engine is operating in a predetermined operating region determined by the engine rotational speed and another engine operation parameter relating to the intake air quantity of the engine, preferably, the intake passage pressure.

Abstract: The feeding rate of fuel supplied to an internal combustion engine is changed by a quantity depending upon the variation rate of the engine load when the engine is decelerating. Thus, the fuel-feeding rate during deceleration can be controlled to an optimum value, causing fuel consumption and engine response to improve.

Abstract: An acceleration fuel enrichment system is disclosed in which if the rate of increase of throttle position is determined as exceeding a predetermined minimum threshold (V.sub.1), asynchronous acceleration enrichment fuel control pulses are developed and effectively added to steady state synchronous base fuel control pulses provided by an engine control microprocessor. When the rate of throttle position increase falls below a preset level, the development of the asynchronous fuel control pulses is terminated and synchronous acceleration enrichment fuel pulses are provided which are effectively added to the base synchronous fuel control pulses. The durations of these synchronous acceleration enrichment pulses are initially fixed, but when a decrease in engine manifold pressure is sensed, these durations are determined in accordance with the rate of change of the magnitude of sensed engine manifold pressure.

Abstract: Electronic fuel injecting method and device for an internal combustion engine, wherein a basic injection time is obtained in accordance with an intake pressure of the engine and an engine rotational speed. During transitions, the basic injection time is corrected in accordance with the operating conditions of the engine so as to determine a fuel injection time. A throttle valve opening correction is increased or decreased in accordance with a changing speed of the throttle valve opening, and subsequently, is attenuated at a predetermined attenuation rate or restored at a predetermined restoration rate. An intake pressure is increased or decreased in accordance with a changing speed of the intake pressure, and subsequently, is attenuated at a predetermined attenuation rate or restored at a predetermined restoration rate. These corrections are combined to obtain a correction value for acceleration and deceleration, and the correction value is used to modify the basic injection time.

Abstract: A method for controlling, according to the L-jetronic fuel injection principle, an internal combustion engine with a fuel injection valve fitted to its intake manifold, and an intake air flow meter. Repeatedly a first quantity representing the desired amount of fuel to be provided to the combustion chambers of the engine during the time period between the next two fuel injection pulse time points is determined, based upon sensed values of certain operational parameters including intake air flow, and a second quantity is determined as the time smoothed value of the first quantity. Optionally further the second quantity may be modified according to engine operational parameters. Simultaneously, at proper injection time points in the engine's operational cycle, the fuel injection valve is opened for a time corresponding to a third quantity which is calculated from the second quantity. A device is also explained, incorporating an electronic computer, which practices this method.

Abstract: A control apparatus is proposed for a fuel metering system of an internal combustion engine having at least one additively functioning warmup enrichment circuit. The apparatus is characterized in that the additive enrichment can be reduced during overrunning. The purpose of this feature is to maintain the cleanest possible exhaust gas even during the warmup phase during overrunning. This is attained, for instance, by means of a logical linkage of an overrunning recognition signal and the output signal of an additively functioning correction circuit for the metering signal.

Abstract: The air-to-fuel ratio of a combustible mixture supplied to an engine is controlled by a feedback loop which includes an integration circuit for integrating the output signal of an oxygen sensor which detects the oxygen concentration in the exhaust gases of the engine, to produce an output voltage. The output of the sensor is applied to the integration circuit through a switch which opens in response to predetermined conditions of the engine whereby the output voltage of the integration circuit is held at a value occurring just before the switch opens.

Abstract: An electronic control type fuel injection system in which, at the time of engine deceleration the fuel injection is stopped, and when resuming to a normal fuel injection from the fuel injection stopped condition, if the reducing rate of the engine speed is smaller than a preset value, a smaller amount of fuel than the amount of fuel injection during normal operation as if fuel injection had not been stopped is first injected and subsequently the amount of fuel to be injected is gradually increased, while when the reducing rate of the engine speed is larger than the preset value, a larger amount of fuel than the fuel injection amount during normal operation is injected.

Abstract: In an electronic fuel injecting method and device for an internal combustion engine, wherein a basic injection time is obtained in accordance with an intake pressure of the engine and an engine rotational speed, and, during transition, the basic injection time is corrected in accordance with the operating conditions of the engine so as to determine a fuel injection time, out of three factors including an after-idle increase correction in which a correction value is increased to a predetermined level when an idle switch is turned "OFF", a throttle valve opening increase or decrease correction in which a correction value is obtained in accordance with a changing speed in opening of a throttle valve, and an intake pressure increase or decrease correction in which a correction value is obtained in accordance with a changing speed of the intake pressure, at least two factors are combined to obtain an increase correction value for acceleration or a decrease correction value for deceleration, and, when the factors a

Abstract: The present invention relates to a fuel cut system for an electronic control system of an engine. When the deceleration of engine rotation is large during fuel cut, the fuel cut is interrupted at the rotational speed higher than when the deceleration is small, and thereby the engine stop caused by the fuel cut during racing period or the like is prevented.

Abstract: An air/fuel ratio feedback control method which is adapted to control the air/fuel ratio of an air/fuel mixture being supplied to an internal combustion engine in response to the output of a means for detecting the concentration of an ingredient in the exhaust gases emitted from the engine. When the engine is operating in a predetermined feedback control region, control of the air/fuel ratio of the air/fuel mixture is carried out by the use of a first coefficient which has a value variable in response to the output of the aforementioned ingredient concentration detecting means, and simultaneously, the value of a second coefficient, which is a mean value of values of the first coefficient, is determined.

Abstract: A fuel supply control method for controlling the fuel supply to an internal combustion engine at deceleration, wherein the valve opening of a throttle valve of the engine is detected while the throttle valve is being closed and each time each pulse of a predetermined sampling signal is generated, a variation in the same valve opening occurring between adjacent pulses of the sampling signal is determined as a control parameter value, and the fuel supply to the engine is interrupted in dependence upon the control parameter value.