Abstract: A slip control system for an automatic transmission of vehicle having fuel cut device for interrupting a fuel supply in a fuel cut zone, including a torque converter, lock-up clutch means provided comprising slip control device for controlling an engaging force of the lock-up clutch ranged from a lock-up condition in which a rotation speed of the input member of the torque converter is substantially the same as the output member of the torque converter to a slip condition in which a predetermined rotation speed difference is produced between the input member and output member, transient control device for controling the engaging force of the lock-up clutch for a predetermined period in connection with a switching operation in the fuel cut device between a fuel supply condition and a fuel cut condition for the engine at a predetermined value between the slip condition and a converter condition in which the lock-up clutch is fully released.

Abstract: A controller controls an engine in cooperation with an automatic transmission which is automatically locked when an operating speed of the engine is higher than a previously established transmission lockup speed. The controller includes an engine power increasing device when an operating engine speed becomes lower than the transmission lockup release speed. The transmission lockup release speed is corrected according to deceleration rates.

Abstract: An ignition timing control system for use in an internal combustion engine equipped with a supercharger, including intake air quantity detecting means for detecting an amount of intake air flowing in an intake air passage defined at the upstream side of the supercharger, engine speed detecting means for detecting the engine speed, ignition timing control means for controlling the ignition timing on the basis of outputs from the intake air quantity detecting means and the engine speed detecting means, intake air condition detecting means for outputting a signal reflecting a substantial pressure of the intake air drawn into a combustion chamber of the engine, and correcting means for correcting the ignition timing in compliance with an output from the intake air condition detecting means.

Abstract: A method and apparatus for electronically controlling injection of fuel into an engine selectively uses fuel injection control based on an intake air flow rate sensing system (e.g. L-J system fuel injection control) and fuel injection control based on a speed density system (e.g. D-J system fuel injection control), this depending upon the amount of intake air. In an engine operating region where a control relationship between these two forms of fuel injection control is constant, e.g. in an operating region where the amount of intake air is low, the relationship is stored. In a region of high air intake, where the relationship no longer holds, the amount of fuel injection in the speed density system is corrected on the basis of the aforementioned relationship.

Abstract: An engine intake system having primary and secondary intake passages leading to the same combustion chamber. The secondary intake passage is provided with an auxiliary throttle valve which is opened under a relatively high load engine operation. The primary and secondary intake passages are respectively provided with first and second fuel injection valves which are controlled by an electronic control unit in accordance with engine operating conditions. The electronic control unit functions to determine a basic fuel supply quantity based on the intake airflow and the engine speed and modify the basic quantity by a compensation factor which is obtained from a compensation map. The compensation map is divided into two zones, the first zone substantially corresponding to the engine operating condition wherein the auxiliary throttle is closed, the second zone substantially corresponding to the engine operating condition wherein the auxiliary throttle valve is opened.

Abstract: An intake system for an internal combustion engine has a primary intake passage and a secondary intake passage both leading to a combustion chamber and respectively having a primary fuel injecting valve and a secondary fuel injecting valve. A control valve is provided in the secondary intake passage for closing the same under light load engine operation and opening the same under heavy load engine operation so that the intake mixture is introduced into the combustion chamber only through the primary intake passage under light load engine operation and through both the primary and secondary intake passages under heavy load operation. A control unit is provided for operating the primary and secondary fuel injecting valves in accordance with the engine operating condition so that fuel is injected only through the primary fuel injecting valve under light load operation.

Abstract: An air-fuel ratio control system for an internal combustion engine wherein a control unit is provided for producing a basic fuel quantity signal based on an engine operating condition. The system includes a feedback system including an O.sub.2 sensor provided in the engine exhaust passage for producing an ON-OFF type signal based on the oxygen content in the engine exhaust gas. The control unit produces a feedback signal which is based on the signal from the O.sub.2 sensor. The control unit further performs a learning control by providing supplementary signals periodically based on the average value of the feedback control signal and the gain of the feedback control is decreased as the learning progresses.