Abstract: A quantity of fuel supplied to an engine so as to allow the air-fuel ratio of a gas mixture to be a target air-fuel ratio is subjected to a feedback correction based on an air-fuel ratio sensor. At the time of the feedback correction, a learning correction is also conducted on the basis of a learning value that is calculated in accordance with a feedback correction value. When the learning value to be used for the learning correction is altered, the feedback correction value is initialized. An initialized feedback correction value is an addition of the feedback correction value before the alteration to a deviation of the respective learning values before and after the alteration of the learning values.

Abstract: An air-fuel ratio controlling apparatus of an engine having an electronic control type automatic change gear ensures the expected acceleration feeling when a power mode is selected in the low load operation with a view to the start or the like of the automobile, and ensures the operation with emphasis upon the fuel cost. An air-fuel ratio adjusting means is provided to correct the air-fuel ratio to be richer during the low load operation of the engine when the power mode is selected than when an economy mode is selected.

Abstract: In a dc electric fuel pump control apparatus for controlling the quantity of fuel supplied to a vehicle engine in accordance with an engine operating parameter condition such as an intake air flow condition or engine speed condition, when controlling a voltage applied to a fuel pump operating motor by closing or opening a fixed-resistor short-circuiting switch circuit in accordance with the magnitude of the operating parameter relative to a predetermined value, an increase or decrease of a battery power source voltage from a predetermined value is detected to increase or decrease the predetermined value of the engine operating parameter. Where a variable resistor is used in place of the fixed resistor, its resistance value in a low battery power source voltage condition is controlled lower than that in a high battery power source voltage condition.

Abstract: The control of a quantity of supply fuel to allow the air-fuel ratio of a gas mixture to be a target air-fuel ratio is conducted by switching between an open loop control and a feedback control using an air-fuel ratio sensor, in response to an operating state of the engine. At the time of the feedback control, a learning correction is carried out using a learning value calculated on the basis of the feedback correction value. At the time of the open loop control, the quantity of the supply fuel is corrected in accordance with the feedback correction value and the learning value immediately before shifting from the feedback control to the open loop control.

Abstract: A fuel injection system for an internal combustion engine comprises a fuel injecting valve, L-jetronic calculating means for calculating the amount of fuel to be injected based upon the output from an air flow meter under an engine operating condition where the amount of intake air is small, D-jetronic calculating means for calculating the amount of fuel to be injected based upon outputs from engine load detecting means and engine rpm detecting means under an engine operating condition where the amount of intake air is large and correcting means for correcting the amount of fuel to be injected upon switchover between the L-jetronic and D-jetronic calculating means in response to engine operating condition changes. As a result, the difference between successive amounts of fuel to be injected is never large. of fuel injected lastly.

Abstract: An internal combustion engine equipped with a supercharger and an idling speed control system comprises a combustion chamber provided with an exhaust passage and an inlet passage in which the supercharger is provided, a throttle valve provided at a downstream portion of the inlet passage compared with the supercharger, an intercooler provided at the downstream portion of the inlet passage compared with the supercharger, a bypass passage provided to the inlet passage for detouring the throttle valve with one end thereof connected with a portion of the inlet passage between the supercharger and the intercooler and the other end thereof connected with another portion of the inlet passage downstream from the intercooler, and an air flow control valve for adjusting intake air mass flow supplied through the bypass passage to the combustion chamber on the occasion of a start of the engine and/or during an idle operation of the engine.

Abstract: An idling speed control system for an internal combustion engine comprises an engine speed sensor, a target idling speed determining unit for setting a target idling speed, an intake air mass flow determining unit for obtaining a difference between an actual idling speed detected by the engine speed sensor and the target idling speed and producing a control signal for determining intake air mass flow supplied to a combustion chamber on the strength of the difference obtained, an intake air mass flow adjusting unit for adjusting intake air mass flow supplied actually to the combustion chamber in response to the control signal, and an extra intake air supplying unit operative to cause the intake air mass flow adjusting unit to start supplying the combustion chamber with extra intake air mass flow when the actual idling speed has gone down to be lower than a first predetermined speed and then to cause the intake air mass flow adjusting unit to cease supplying with the extra intake air mass flow when the actual i

Abstract: A fuel intake system for a supercharged automotive engine having at least one engine cylinder with first and second fuel intake ports and exhaust port comprises first fuel intake passage communicated at one end to the first fuel intake port and at the other end to the supercharger through a first throttle valve, and a second fuel intake passage communicated at one end to the second fuel intake port and at the other end to the supercharger through a second throttle valve. These intake and exhaust ports are adapted such that the first fuel intake port opens at a timing preceding the closure of the exhaust port and the second fuel intake port opens after the opening of the first fuel intake port.

Abstract: An engine having a turbo-supercharger comprised of a blower in the intake passage and an exhaust gas turbine in the exhaust passage. A charging pressure limiting device includes a pressure relief passage in the intake system or a turbine bypass passage in the exhaust system which is provided with a control valve. A control circuit is provided for limiting the peak charging pressure. The control circuit includes a limit signal generating circuit for providing a limit signal which decreases in response to an increase in the engine speed under a high speed range, a comparator for comparing the limit signal with the actual charging pressure signal and producing a control signal when the charging pressure signal reaches or exceeds the limit signal so that the charging pressure does not exceed the limit value which decreases in response to an increase in the engine speed under a high speed range.

Abstract: An internal combustion engine having a turbo-supercharger and a catalytic exhaust gas purifying device located downstream of the exhaust gas turbine. The exhaust passage is provided with a bypass passage in parallel with the exhaust gas turbine and a valve is provided for opening the bypass passage when the engine operating temperature is below a predetermined value so that the exhaust gas is passed through the bypass passage to the catalytic device. This arrangement is effective to heat the catalytic device rapidly to a working temperature.