Abstract: A method of controlling a hybrid automobile is provided. Only a drive force of the motor is outputted to wheels by stopping the engine while operating the motor when a required drive force is below a predetermined switch value, and at least a drive force of the engine is outputted to the wheels by operating at least the engine when the required drive force is above the switch value. The method includes estimating, when the required drive force is below the switch value, a switching possibility of the required drive force increasing above the switch value, operating the engine so that a temperature of a catalyst becomes a first temperature when the estimated switching possibility is above a predetermined level, and operating the engine so that the temperature of the catalyst becomes a second temperature lower than the first temperature when the estimated switching possibility is below the predetermined level.

Abstract: A method of controlling a hybrid automobile is provided. Only a drive force of the motor is outputted to wheels by stopping the engine while operating the motor when a required drive force is below a predetermined switch value, and at least a drive force of the engine is outputted to the wheels by operating at least the engine when the required drive force is above the switch value. The method includes estimating, when the required drive force is below the switch value, a switching possibility of the required drive force increasing above the switch value, operating the engine so that a temperature of a catalyst becomes a first temperature when the estimated switching possibility is above a predetermined level, and operating the engine so that the temperature of the catalyst becomes a second temperature lower than the first temperature when the estimated switching possibility is below the predetermined level.

Abstract: An engine-control system is structured in such a way that a timing for closing the intake valve is retarded and the air-fuel ratio is so set as to become a rich air-fuel ratio richer than, for example, the stoichiometric air-fuel ratio, in a region where the load is low. On the other hand, in a region where the load is high, the timing for closing the intake valve is set earlier and the air-fuel ratio is so set as to become a lean air-fuel ratio leaner than, for example, the stoichiometric air-fuel ratio.

Abstract: A controller for a supercharged engine includes a supercharger for supercharging intake air, an intercooler for cooling the intake air discharged from the supercharger, a valve timing varying device for varying valve timing so that an overlapping term, in which both intake and exhaust valves open, is longer when an engine speed is relatively high than when the engine speed is relatively low, and a controller for controlling the valve timing varying device so that when the overlapping term is short at relatively low speed of the engine, the intake valves close at a timing later than a timing at which the intake valves close when the overlapping term is long at relatively high speed of the engine.

Abstract: Disclosed is an exhaust gas recirculation system for an engine having a high compression ratio or with a supercharger. An outside EGR duct connecting the exhaust system to the intake system is provided with a first control valve, which has a second outside EGR duct bypassing the first control valve. The second EGR duct has a second EGR control valve and a cooler. When the engine exists in an extremely low load state, the first and second control valves are closed to inhibit the outside EGR. In the light load state, the first control valve is opened while the second control valve is closed, thereby allowing recirculation of the EGR gases having high temperature and reducing the pumping loss.

Abstract: An engine induction system includes intake passages connected to inlet ports of an engine, an injector provided in the intake passage for injecting fuel in an intake plenum between the injector and the inlet port, the injector being disposed in such a position that the volume of the intake plenum is greater than the predetermined stroke volume. This ensures improved vaporization and atomization of fuel and mixing of fuel and air, and improves the combustibility and increases the charging efficiency of use of latent heat of vaporization.

Abstract: An engine air-fuel ratio control system in which the engine operating range is divided into a light load, medium load and heavy load regions. In the light load region, a control of the fuel supply is made so as to provide a mixture of leaner than the stoichiometric value. In the medium load region, a feedback control is made based on the signal from an O.sub.2 sensor and, in the heavy load region, a control is made to provide a richer mixture. In the transient between the light load and medium load regions, the air-fuel ratio is changed with a rate which changes in accordance with the rate of change in the engine load.