Abstract: A control system controls a hybrid vehicle having an engine for rotating a drive axle, an electric motor for assisting the engine in rotating the drive axle with electric energy and converting kinetic energy of the drive axle into electric energy, and an electric energy storage unit or a capacitor for supplying electric energy to the electric motor and storing electric energy outputted by the electric motor.

Abstract: A system for controlling fuel injection in an internal combustion engine such that when the target air-fuel ratio is switched from a rich value to a lean value, the air-fuel ratios are switched to the lean value by sequentially decreasing the amount of fuel injected into the cylinders, for example in a four cylinder engine into the #1, #2, #3 and #4 cylinders, with predetermined time differences. During this time, an electronic air control valve (EACV) is controlled in such a manner that it is stepwise opened with the switching of the air-fuel ratio s for the #1, #2, #3 and #4 cylinders, thereby causing the engine torque to remain the same to prevent the generation of a torque shock. When the target air-fuel ratio has been switched from the lean level to the rich level, the amounts of fuel injected into the #1, #2, #3 and #4 cylinders are controlled in such a manner that they are sequentially increased with predetermined time differences, and the EACV is controlled in such a manner that it is stepwise closed.

Abstract: A control system is provided for a hybrid vehicle including an internal combustion engine, a drive shaft driven by the engine, a generator for converting kinetic energy of the drive shaft to electrical energy to generate electric power, and an electrical storage device for storing electrical energy output from the generator. Deceleration of the engine is detected. Supply of fuel to the engine is interrupted during the deceleration of the engine. An amount of intake air supplied to the engine is controlled such that the amount of intake air supplied to the engine is increased when the generator regenerates electrical energy during the deceleration of the engine. Calculation is made of an amount of electrical energy to be regenerated by the generator during the deceleration of the engine. An output from the generator is controlled based on the amount of electrical energy calculated.

Abstract: There is provided a control system for a hybrid vehicle including an internal combustion engine, a drive shaft driven by the engine, a motor operable on electrical energy for driving the drive shaft, and electrical storage device for supplying electrical energy to the motor. An amount of assistance of the motor to the engine by driving the drive shaft is calculated based at least on load on the engine. An output from the motor is controlled based on the amount of assistance of the motor to the engine. It is determined whether conditions are satisfied for a lean operating mode of the engine in which an air-fuel ratio of a mixture supplied to the engine is controlled to a leaner value than a stoichiometric value.

Abstract: A control system is provided in an internal combustion engine in which a valve timing such as an opening time point and lift amount of an intake valve can be switched to a low-speed or high-speed valve timing within a lean-burn control range established in accordance with the operational state, such as an intake pipe internal absolute pressure and an engine revolution number of the engine, wherein an air-fuel ratio of an air-fuel mixture supplied to the internal combustion engine is enriched for a predetermined time when the valve timing is switched from the low-speed valve timing to the high-speed valve timing while carrying out a lean-burn control.

Abstract: A system for controlling fuel injection in an internal combustion engine such that when the target air-fuel ratio is switched from a rich value to a lean value, the air-fuel ratios are switched to the lean value by sequentially decreasing the amount of fuel injected into the cylinders, for example in a four cylinder engine into the #1, #2, #3 and #4 cylinders, with predetermined time differences. During this time, an electronic air control valve (EACV) is controlled in such a manner that it is stepwise opened with the switching of the air-fuel ratios for the #1, #2, #3 and #4 cylinders, thereby causing the engine torque to remain the same to prevent the generation of a torque shock. When the target air-fuel ratio has been switched from the lean level to the rich level, the amounts of fuel injected into the #1, #2, #3 and #4 cylinders are controlled in such a manner that they are sequentially increased with predetermined time differences, and the EACV is controlled in such a manner that it is stepwise closed.

Abstract: A system for controlling fuel injection in an internal combustion engine such that when the target air-fuel ratio is switched from a rich value to a lean value, the air-fuel ratios are switched to the lean value by sequentially decreasing the amount of fuel injected into the cylinders, for example in a four cylinder engine into the #1, #2, #3 and #4 cylinders, with predetermined time differences. During this time, an electronic air control valve (EACV) is controlled in such a manner that it is stepwise opened with the switching of the air-fuel ratios for the #1, #2, #3 and #4 cylinders, thereby causing the engine torque to remain the same to prevent the generation of a torque shock. When the target air-fuel ratio has been switched from the lean level to the rich level, the amounts of fuel injected into the #1, #2, #3 and #4 cylinders are controlled in such a manner that they are sequentially increased with predetermined time differences, and the EACV is controlled in such a manner that it is stepwise closed.

Abstract: An air-fuel ratio control system for an internal combustion engine having a fuel injection valve for each cylinder and an electronic air control valve (EACV) for controlling intake air bypassing the engine throttle valve. When the target air-fuel ratio is switched over from a rich value to a lean value, the amounts of fuel injected into the cylinders, for example, #1, #2, #3 and #4 cylinders are controlled so that they are sequentially decreased at predetermined intervals, and the EACV is controlled to be opened stepwise. This causes a decrease in engine torque generated by the switching-over of the target air-fuel ratio to be offset by an increase in engine torque generated by an increase in amount of air drawn, thereby preventing the generation of a torque shock. At this time, the target opening degree of the EACV is corrected based on the magnitude of the interval and the magnitude of a loading of the internal combustion engine, thereby further effectively preventing the generation of the torque shock.