Abstract: In a thermostat failure diagnosis apparatus for an internal combustion engine in which a failure diagnosis of a thermostat can be effectively made, in the case where, after starting of the engine, an intake air quantity of the engine or a parameter related to the intake air quantity is equal to or higher than a predetermined value, and a cooling water temperature is equal to or higher than an intake air temperature (outside air temperature), on the basis of a time in which a rising quantity in the cooling water temperature at an upstream side of the thermostat reaches a predetermined value, or a time in which the cooling water temperature rises to a predetermined temperature, the failure of the thermostat is judged. By this, the failure diagnosis of the thermostat can be rationally made only when the engine generating heat quantity is large to some degree to prevent erroneous diagnosis.

Abstract: In a thermostat failure diagnosis apparatus for an internal combustion engine in which a failure diagnosis of a thermostat can be effectively made, in the case where, after starting of the engine, an intake air quantity of the engine or a parameter related to the intake air quantity is equal to or higher than a predetermined value, and a cooling water temperature is equal to or higher than an intake air temperature (outside air temperature), on the basis of a time in which a rising quantity in the cooling water temperature at an upstream side of the thermostat reaches a predetermined value, or a time in which the cooling water temperature rises to a predetermined temperature, the failure of the thermostat is judged.

Abstract: In a thermostat failure diagnosis apparatus for an internal combustion engine in which a failure diagnosis of a thermostat can be effectively made, in the case where, after starting of the engine, an intake air quantity of the engine or a parameter related to the intake air quantity is equal to or higher than a predetermined value, and a cooling water temperature is equal to or higher than an intake air temperature (outside air temperature), on the basis of a time in which a rising quantity in the cooling water temperature at an upstream side of the thermostat reaches a predetermined value, or a time in which the cooling water temperature rises to a predetermined temperature, the failure of the thermostat is judged.

Abstract: A self-diagnosis system for a vehicle, with which it is possible, without requiring skill and practice, to realize running according to a running pattern and easily and certainly cause an ECU to execute a self-diagnosis.

Abstract: A fault diagnosing apparatus for evapopurge systems, including a device adapted to detect a pressure in the interior of an evapopassage including a fuel tank, a depressurization device adapted to close a first valve provided in an atmosphere-opened port of a canister and depressurize the interior of the evapopassage by a negative pressure occurring in a suction passage of an internal combustion engine, a repressurization device adapted to close a second valve after the operation of the depressurization device finishes, to repressurize the interior of the evapopassage, and a fault judgement device adapted to allow a judgement, which is based on an output from the pressure detecting device, that an evapopurge system is abnormal to be given on condition that the depressurization and repressurization devices are operated plural times.

Abstract: In a SOHC type internal combustion engine having a single camshaft, a fuel injector is provided for directly injecting a fuel into a combustion chamber, and an intake port is provided such that one end of the intake port is open at intake openings to the combustion chamber. The intake port extends toward the top face of a cylinder head between the camshaft and two intake valves, such that at least a part of the intake port passes through a region between the shortest lines connecting respective head portions of the intake valves and the camshaft.

Abstract: In a SOHC type internal combustion engine having a single camshaft, a fuel injector is provided for directly injecting a fuel into a combustion chamber, and an intake port is provided such that one end of the intake port is open at intake openings to the combustion chamber. The intake port extends toward the top face of a cylinder head between the camshaft and two intake valves, such that at least a part of the intake port passes through a region between the shortest lines connecting respective head portions of the intake valves and the camshaft.

Abstract: In a SOHC type internal combustion engine having a single camshaft, a fuel injector is provided for directly injecting a fuel into a combustion chamber, and an intake port is provided such that one end of the intake port is open at intake openings to the combustion chamber. The intake port extends toward the top face of a cylinder head between the camshaft and two intake valves, such that at least a part of the intake port passes through a region between the shortest lines connecting respective head portions of the intake valves and the camshaft.

Abstract: In a swash plate type axial piston pump, a swash plate 23 is fixed and supported in a cabinet while being inclined with respect to the center axial line of a rotary shaft 3. A cylinder block 15 having a plurality of cylinders 13 is attached to the rotary shaft 3 so that the cylinder block 15 slides of the rotary shaft 3 in the axial direction thereof and is rotated integrally therewith. Each one end of a plurality of pistons 21 is slidingly engaged with the cylinder 13 and the other end thereof is abutted against the swash plate 23 through a shoe 25. A valve plate 31 having a suction port 33 and a discharge port 35 is disposed so as to be abutted against the inner surface of the cabinet 1 and the bottom the cylinder block 15 so that a suction path 39 and a discharge path 41 in the cabinet 1 are selectively communicated with a pump chamber 14 in each cylinder through the suction port 33 and the discharge port 35.

Abstract: A fuel feeding system is provided for an internal combustion engine to permit appropriate feeding of fuel in accordance with the state of operation of the engine. A fuel line is arranged as a recirculation circuit between a fuel injector and a fuel tank. A low-pressure fuel pump is arranged in an upstream part of the fuel line. A high-pressure fuel pump is arranged between the fuel pump and the injector. A high-pressure regulator is arranged in a fuel line portion on a downstream side of the regulator to control the pressure of fuel delivered from the pump. A bypass line connects another fuel line portion on an upstream side of the regulator and the fuel line portion each other. A switching valve is arranged in the bypass line to open or close the same. A low-pressure regulator controls the pressure of fuel in the fuel line portion at a pressure lower than a control pressure set by the regulator while the switching valve is open.

Abstract: A variable compression ratio apparatus is provided for use in an internal combustion engine. The apparatus has an eccentric sleeve rotatably arranged in one of pivot portions at opposite ends of a connecting rod so as to make a bearing hole of the connecting rod and a pin, which extends through the bearing hole, eccentric relative to each other. The apparatus also has an eccentric sleeve lock device capable of fixing rotation of the eccentric sleeve at a desired position. The lock device includes a pin member engageable with one of engagement portions formed in the eccentric sleeve and a piston-type fluid pressure drive system. The drive system is adapted to produce a pressure difference between fluid pressure chambers formed at opposite sides of a piston portion, which is connected to the pin member, in a state that the fluid pressure chambers are applied with a prescribed fluid pressure, whereby the piston portion is moved to drive the pin member.

Abstract: A method of and an apparatus for controlling the air fuel ratio of an internal combustion engine by which the air fuel ratio can be controlled so that the exhaust gas purifying efficiency of a catalytic converter for purifying exhaust gas of the engine may be maximum. In the apparatus, exhaust gas of the engine is first passed through a catalytic converter and then is introduced into an oxygen concentration sensor of the .lambda. type. When the air fuel ratio is compulsorily varied, the compulsorily varied condition of the air fuel ratio such as an average of variations of the air fuel ratio (average air fuel ratio) is corrected in accordance with an output of the oxygen concentration sensor thereby to control the air fuel ratio so that the purifying efficiency of the exhaust gas purifying catalytic converter may be maximum.

Abstract: An air/fuel ratio control system is provided for use with an internal combustion engine. The system includes a first air/fuel ratio detector arranged on an upstream side of a catalytic converter so as to detect the air/fuel ratio of the engine from components of exhaust gas, a second air/fuel ratio detector arranged in the exhaust system and having a detection response speed slower than the first air/fuel ratio detector, a device for controlling the air/fuel ratio of the engine on the basis of results of a comparison between a detection value from the first air/fuel ratio detector and a predetermined first reference value, a device for effecting a correction to the control of the air/fuel ratio by the air/fuel ratio control device on the basis of results of a comparison between a detection value from the second air/fuel ratio detector and a predetermined second reference value, and a device for shifting the second reference value to a lean air/fuel ratio side in a specific operation state of the engine.

Abstract: An air/fuel ratio control system is provided for use with an internal combustion engine. The system includes an air/fuel ratio detector arranged on an upstream side of a catalytic converter so as to detect the air/fuel ratio of the internal combustion engine from components of exhaust gas, a device for controlling the air/fuel ratio of the internal combustion engine on the basis of results of a comparison between a detection value from the air/fuel ratio detector and a predetermined reference value; and a device for shifting the reference value to a lean air/fuel ratio side in a specific operation state of the internal combustion engine.

Abstract: A feedback control system for an air-fuel ratio according to the present invention comprises a first oxygen sensor for detecting the oxygen concentration of exhaust gas flowing through a first exhaust pipe of an internal combustion engine, a second oxygen sensor for detecting the oxygen concentration of the exhaust gas passed through an exhaust gas disposer in a common exhaust passage which is connected with both first and second exhaust pipes of the engine, and an electronic control unit for calculating the amount of fuel supply to each cylinder of the engine in accordance with the oxygen concentration of the exhaust gas detected by means of the first oxygen sensor. The electronic control unit contains therein a correction circuit for correcting the amount of fuel supply to that cylinder of the engine which is associated with the second exhaust pipe, in accordance with the oxygen concentration of the exhaust gas detected by means of the second oxygen sensor.

Abstract: Disclosed herein is an air/fuel ratio control system for an internal combustion engine. The system includes a first oxygen density sensor element, a second oxygen density sensor element having a slower detection response speed than the first sensor element, an air/fuel ratio control unit for controlling the air/fuel ratio of the engine on the basis of results of a comparison between a detection value from the first sensor element and a standard value, and an air/fuel ratio control correction means for effecting a correction to the air/fuel ratio control by the air/fuel ratio control unit on the basis of results of comparison between a detection value from the second sensor element and a second standard value. An air/fuel ratio controlling oxygen density sensor is also disclosed.

Abstract: An air/fuel ratio control system is provided for an internal combustion engine. The system includes first and second oxygen density sensors, an air/fuel ratio control device and a standard-value changing device. The first oxygen density sensor is arranged on an upstream side of a catalytic converter, while the second oxygen density sensor is provided either inside or on a downstream side of the catalytic converter. The air/fuel control device controls the air/fuel ratio of the internal combustion engine on the basis of results of comparison between a detection value from one of the first and second oxygen density sensors and a predetermined standard value. The standard-value changing device changes the standard value on the basis of outputs from the first and second oxygen density sensors.

Abstract: Flammable fine particles (particulates) consisting principally of carbon and hydrocarbons are discharged from a diesel engine to its exhaust system. A diesel particulate oxidizer (DPO) is disposed in the exhaust passage for collecting and burning the particulates without allowing the particulates to be discharged directly to the atmosphere. This DPO comprises a ceramic foam with catalyst. When the quantity of particulates collected is above a predetermined value, the DPO will undergo clogging. To prevent this, a high temperature gas containing oxygen is fed to the DPO to burn (regenerate) the collected particulates. In order to accelerate the normal regeneration of the DPO, there are provided a regeneration means for making a retard control of the fuel injection timing in the diesel engine, and a regeneration timing control means for controlling the operation of the regeneration means. Further, there is provided a regeneration timing detection means for detecting the regeneration timing of the DPO.

Abstract: A particulate oxidizer system for a diesel engine comprises a diesel particulate oxidizer (DPO) in the exhaust line to collect and burn particulates in the exhaust. The DPO comprises ceramic foam with a catalyst. When the quantity of particulates in the DPO reaches a predetermined value, high temperature gas containing oxygen is fed to the DPO to burn off (regenerate) the collected particulates. This is achieved by retard control of the injection timing under control of an engine control unit (ECU). A regeneration timing detection means detects the regeneration timing in the DPO. When the quantity of particulates in the DPO falls below a predetermined value, the ECU provides a signal to increase the idling revolution of the engine.

Abstract: An apparatus for controlling the supply of air to a burner used to recombust diesel particulates trapped in a ceramic filter. The inventive control apparatus includes an exhaust bypass line that bypasses the filter, an air supply line leading to a burner associated with the filter, a flow control valve that adjusts the cross-sectional area for the air flow in the air supply line, a relief valve that maintains a constant difference between pressures at points upstream and downstream of the flow control valve, and a control unit that controls the degree of opening of the flow control valve. With the invention, precise control over the flow rate of secondary air is ensured.