Abstract: An engine includes: a piston including a cavity; a cylinder head configured so as to form a combustion chamber having a pent roof shape; a fuel injection valve configured to inject fuel from a second half of a compression stroke until a first half of an expansion stroke; and a spark plug arranged at a position corresponding to an upper side of the cavity. Injection openings which are arranged in a circumferential direction surrounding a longitudinal axis of the valve and through each of which the fuel is injected in a direction inclined relative to the longitudinal axis by a predetermined angle is formed such that when a height of a ceiling of the combustion chamber at a position corresponding to an edge end portion of the cavity in an injection direction of the injection opening is large, the injection angle of the injection opening is large.

Abstract: An engine includes: a piston including a cavity; a cylinder head configured to form a combustion chamber having a pent roof shape; a fuel injection valve configured to inject fuel from a second half of a compression stroke until a first half of an expansion stroke; and a spark plug arranged at a position corresponding to an upper side of the cavity. Injection openings are arranged in a circumferential direction surrounding a longitudinal axis of the valve. The combustion chamber at a compression top dead center is divided into a plurality of fuel injection regions, located in respective injection directions of the injection openings, by vertical surfaces extending radially from the longitudinal axis through a middle between adjacent injection openings. When a volume of the fuel injection region located in the injection direction of the injection opening is large, an opening area of the injection opening is large.

Abstract: When a specified learning execute condition is established, the high-pressure pump is stopped so that the fuel pressure in the high pressure fuel passage is made equal to the fuel pressure in the low pressure fuel passage. A low pressure fuel control is executed to control a driving voltage of the low-pressure pump based on the operational characteristic of the low-pressure pump. A driving voltage of the low-pressure pump is gradually corrected so that the difference between the detected high fuel pressure and a target low fuel pressure becomes small. A driving voltage correcting amount is learned as the control error of the low pressure fuel control. The driving voltage correction amount is stored as the learning correction amount, and the driving voltage of the low-pressure pump is corrected by means of the learning correction amount.

Abstract: An engine includes: a piston including a cavity; a cylinder head configured so as to form a combustion chamber having a pent roof shape; a fuel injection valve configured to inject fuel in a period from a second half of a compression stroke until a first half of an expansion stroke; and a spark plug arranged at a position corresponding to an upper side of the cavity. Injection openings which are arranged in a circumferential direction surrounding a longitudinal axis of the valve and through each of which the fuel is injected in a direction inclined relative to the longitudinal axis by a predetermined angle is formed such that when a height of a ceiling of the combustion chamber at a position corresponding to an edge end portion of the cavity in an injection direction of the injection opening is large, the injection angle of the injection opening is large.

Abstract: An engine includes: a piston including a cavity; a cylinder head configured to form a combustion chamber having a pent roof shape; a fuel injection valve configured to inject fuel from a second half of a compression stroke until a first half of an expansion stroke; and a spark plug arranged at a position corresponding to an upper side of the cavity. Injection openings are arranged in a circumferential direction surrounding a longitudinal axis of the valve. The combustion chamber at a compression top dead center is divided into a plurality of fuel injection regions, located in respective injection directions of the injection openings, by vertical surfaces extending radially from the longitudinal axis through a middle between adjacent injection openings. When a volume of the fuel injection region located in the injection direction of the injection opening is large, an opening area of the injection opening is large.

Abstract: An output limiting control is carried out for limiting an output of a driving source when an acceleration pedal as well as a brake pedal is operated at the same time. An acceleration opening degree for a malfunction diagnosis is set based on a detected acceleration opening degree. A required output value for the malfunction diagnosis is calculated based on the acceleration opening degree for the malfunction diagnosis. A malfunction determining threshold is set in accordance with the required output value. An estimated output value of the driving source is compared with the malfunction determining threshold in order to determine whether there is a malfunction in a control system for the driving source. The acceleration opening degree for the malfunction diagnosis is limited to a predetermined limiting value, when the acceleration and brake pedal are operated at the same time.

Abstract: An output limiting control is carried out for limiting an output of a driving source when an acceleration pedal as well as a brake pedal is operated at the same time. An acceleration opening degree for a malfunction diagnosis is set based on a detected acceleration opening degree. A required output value for the malfunction diagnosis is calculated based on the acceleration opening degree for the malfunction diagnosis. A malfunction determining threshold is set in accordance with the required output value. An estimated output value of the driving source is compared with the malfunction determining threshold in order to determine whether there is a malfunction in a control system for the driving source. The acceleration opening degree for the malfunction diagnosis is limited to a predetermined limiting value, when the acceleration and brake pedal are operated at the same time.

Abstract: When a specified learning execute condition is established, the high-pressure pump is stopped so that the fuel pressure in the high pressure fuel passage is made equal to the fuel pressure in the low pressure fuel passage. A low pressure fuel control is executed to control a driving voltage of the low-pressure pump based on the operational characteristic of the low-pressure pump. A driving voltage of the low-pressure pump is gradually corrected so that the difference between the detected high fuel pressure and a target low fuel pressure becomes small. A driving voltage correcting amount is learned as the control error of the low pressure fuel control. The driving voltage correction amount is stored as the learning correction amount, and the driving voltage of the low-pressure pump is corrected by means of the learning correction amount.

Abstract: When it is determined that accelerator operation and brake operation are performed at the same time based on the output values of an accelerator sensor and a stop lamp switch, a torque of an engine is reduced based on a brake pedal force which is computed based on a pressure in a negative pressure chamber of a master bag and a brake oil pressure.

Abstract: A controller is provided to an engine including a variable valve timing unit for manipulating a valve timing of an intake valve of the engine. The controller includes an idle-continuation determining unit for determining whether an idling operation of the engine is in a continued state. The controller further includes a torque reserve control unit for executing a torque reserve control to advance the valve timing and increase an intake air quantity of the engine within a combustion limit of the engine when the idle-continuation determining unit determines that the idling operation is in the continued state. The controller further includes a torque correction unit for executing a torque correction control to retard the valve timing in the torque reserve control in at least one of conditions where: an auxiliary device exerts a load; the load is increased; and a vehicle starts moving.

Abstract: A variable valve timing adjusting mechanism includes one-way valves in a hydraulic supply passage in an advance hydraulic chamber and in a retard hydraulic chamber respectively and a drain oil passage bypassing each of the one-way valves disposed in parallel in the hydraulic supply passage of each hydraulic chamber. Drain switching valves are disposed in the respective drain oil passages. A controller opens the drain switching valve in a side of the hydraulic chamber where oil is discharged when a deviation between a target displacement angle and an actual displacement angle is more than a predetermined value to perform the maximum speed control for driving the adjusting mechanism in a direction of the target displacement angle at the maximum speed.

Abstract: One-way valves are provided in a hydraulic pressure supply passage in an advance hydraulic chamber and a hydraulic pressure supply passage in a retard hydraulic chamber respectively. A drain oil passage bypassing each of the one-way valves is provided in the hydraulic pressure supply passage in the each hydraulic chamber to be in parallel therewith. A drain switching valve is provided in the each drain oil passage. A drain switching control function for switching the hydraulic pressure driving the each drain switching valve is integral with a function of the hydraulic control valve for controlling the hydraulic pressure supplied to the advance hydraulic chamber and the retard hydraulic chamber. It is determined whether the responsiveness of an advance/retard operation is in a normal range based upon a changing rate of the VTC displacement angle during advance/retard operating, thereby determining presence/absence of abnormality in the advance/retard operation.

Abstract: In a cooling system of an internal combustion engine, coolant flowing through a radiator and bypassing the radiator are mixed in a flow control valve controlled by ECU on the basis of signals provided by sensors such as a coolant temperature sensor, so that the coolant is circulated by an electric pump to control the coolant temperature for the internal combustion engine. A desired coolant temperature is changed according to the operating condition of the internal combustion engine, the traveling condition of a vehicle and the ambient condition. A fluid control valve controls the flow rate of cooling water through the bypass passage. The flow control valve is diagnosed for abnormalities. If it is determined that the flow control valve is in an abnormal condition, a heat generation rate reducing control operation is executed to reduce the heat generation rate of the internal combustion engine.

Abstract: In a cooling system of an internal combustion engine, coolant flowing through a radiator and bypassing the radiator are mixed in a flow control valve controlled by ECU on the basis of signals provided by sensors such as a coolant temperature sensor, so that the coolant is circulated by an electric pump to control the coolant temperature for the internal combustion engine. A desired coolant temperature is changed according to the operating condition of the internal combustion engine, the traveling condition of a vehicle and the ambient condition. Thus, the temperature of the coolant flowing into the internal combustion engine is changed properly so that frictional resistance in the engine and exhaust gas may be reduced and the internal combustion engine may be kept at its most efficient temperature near a detonation limit temperature.

Abstract: In a cooling system of an internal combustion engine, coolant flowing through a radiator and bypassing the radiator are mixed in a flow control valve controlled by ECU on the basis of signals provided by sensors such as a coolant temperature sensor, so that the coolant is circulated by an electric pump to control the coolant temperature for the internal combustion engine. A desired coolant temperature is changed according to the operating condition of the internal combustion engine, the traveling condition of a vehicle and the ambient condition. Thus, the temperature of the coolant flowing into the internal combustion engine is changed properly so that frictional resistance in the engine and exhaust gas may be reduced and the internal combustion engine may be kept at its most efficient temperature near a detonation limit temperature.

Abstract: Erroneous malfunction determination of an oxygen sensor is avoided by consideration of combustible substance penetrating to an air electrode side of the oxygen sensor. The combustible substance is determined whether it has penetrated to the air electrode of the oxygen sensor. If it is determined so, then it is determined whether the oxygen deficiency has disappeared, and the sensor malfunction determination operation is disabled until the oxygen deficiency at the air electrode is eliminated. At the same time, malfunction determination is also disabled.

Abstract: A system for exactly detecting any unstable state in which disturbance is caused on the output value of a thermal air flowmeter for measuring intake air flow rate, thereby preventing or promptly suppressing the generation of undesirable states such as a variation in the air-fuel ratio or rough idling.The system has an upstream intake air temperature sensor for detecting the temperature of the intake air before entering an air cleaner element, the above-mentioned thermal air flowmeter, and a downstream air temperature sensor for detecting the temperature of the intake air after passing the thermal air flowmeter. The system determines that the air flow rate output of the thermal air flowmeter is unstable, when the difference between the air temperature values detected by the upstream and downstream intake air temperature sensors exceeds a predetermined value, and executes a control process which has been determined to cope with such an unstable state.

Abstract: An internal combustion engine control apparatus is provided which is capable of performing various controls based upon the air quantity immediately after a current heated element of a hot wire air flow meter is heated to a predetermined temperature. When a key switch is rotated to an "ON" position, a large current flows through the air flow meter and the detected intake air quantity greatly exceeds the actual intake air quantity and therefore during the warm up period of the heater, the fuel injection amount is a constant corresponding to the coolant temperature until the engine speed reaches 500 rpm. Likewise during this warm up period, the smoothing processing of the fuel injection quantity is stopped.

Abstract: A fuel vapor purging control system is provided. This system includes a fuel vapor collection canister, a purge control valve for controlling a purge flow rate of fuel vapors purged from the canister, a purge air induction passage communicating between the canister and an air inlet port which is exposed to atmospheric pressure, an air pump for supplying pressurized air to the canister through the purge air induction passage, a pressure sensor for detecting negative pressure in an induction system of the engine, and a purge air control unit. When the engine falls to a relatively high load level and the negative pressure becomes smaller than a preselected threshold value, the purge air control unit directs the pressurized air from the air pump to the canister for assuring a desired purge flow rate during each engine operation.