Abstract: An amount of fuel injected into an internal combustion engine is controlled to adjust an air-fuel ratio. An air-fuel ratio sensor is disposed upstream of a three-way catalyst. An ammonia sensor is disposed downstream of the three-way catalyst. Main feedback control based on the air-fuel ratio sensor is performed such that the air-fuel ratio of exhaust gas becomes close to a target air-fuel ratio in the neighborhood of a stoichiometric air-fuel ratio. Sub-feedback control is performed on the basis of an output value of the ammonia sensor.

Abstract: A first cylinder and a second cylinder are provided. A first exhaust pipe is connected to the first cylinder and a second exhaust pipe is connected to the second cylinder. A communicating pipe connects together an intermediate portion of the first exhaust pipe with an intermediate portion of the second exhaust pipe. An exhaust gas control catalyst is arranged in the second exhaust pipe downstream of the portion to which the communicating pipe is connected. Exhaust gas amount reducing devices are provided which reduce the amount of exhaust gas that flows from the first exhaust pipe into the second exhaust pipe through the communicating pipe during execution of rich/lean burn control which performs combustion with an air-fuel ratio of an air-fuel mixture that is richer than the stoichiometric air-fuel ratio in one of the first cylinder and second cylinder and performs combustion with an air-fuel ratio of an air-fuel mixture that is leaner than the stoichiometric air-fuel ratio in the other cylinder.

Abstract: A hybrid vehicle including an engine, a generator capable of generating power by being driven by the engine, an electric motor capable of running on power supplied from the generator, a power split device that transmits output from the engine to a driving wheel and the generator and also transmits output from the electric motor to the driving wheel, and a main ECU that controls an output ratio of the engine and an output ratio of the electric motor using the power split device according to the running state of the vehicle. When the operating mode of the engine is switched between a lean burn operating mode and a stoichiometric burn operating mode, the main ECU selectively increases and decreases the output ratio of the electric motor so that the total output, which is the combined output of the engine and the electric motor, is constant.

Abstract: The control device of the internal combustion engine appropriately controls plural exhaust valves to effectively perform sulfur poisoning recovery in an exhaust gas purifying catalyst. The control device controls the internal combustion engine which performs lean burn. The exhaust system of the internal combustion engine includes: first exhaust valves and second exhaust valves provided in each of the plural cylinders; a first exhaust passage communicating with the first exhaust valves; a second exhaust passage communicating with the second exhaust valves; a first exhaust gas purifying catalyst provided at least one of the first exhaust passage and the second exhaust passage; and a second exhaust gas purifying catalyst provided on an exhaust passage downstream of a junction of the first exhaust passage and the second exhaust passage.

Abstract: In a V-type six cylinder engine, cylinder groups are provided in which a plurality of cylinders are arranged divided into left and right first and second banks. An intake pipe, a first exhaust pipe, and a second exhaust pipe are connected to the cylinder groups of the banks. A first upstream three-way catalyst and a first control valve are provided in one exhaust pipe while a second upstream three-way catalyst and a second control valve are provided in the other exhaust pipe. The exhaust pipes are communicated together upstream of the upstream three-way catalysts and the control valves by a communicating pipe. A third control valve that adjusts the flowrate of exhaust gas is provided in the communicating pipe.

Abstract: A first cylinder and a second cylinder are provided. A first exhaust pipe is connected to the first cylinder and a second exhaust pipe is connected to the second cylinder. A communicating pipe connects together an intermediate portion of the first exhaust pipe with an intermediate portion of the second exhaust pipe. An exhaust gas control catalyst is arranged in the second exhaust pipe downstream of the portion to which the communicating pipe is connected. Exhaust gas amount reducing devices are provided which reduce the amount of exhaust gas that flows from the first exhaust pipe into the second exhaust pipe through the communicating pipe during execution of rich/lean burn control which performs combustion with an air-fuel ratio of an air-fuel mixture that is richer than the stoichiometric air-fuel ratio in one of the first cylinder and second cylinder and performs combustion with an air-fuel ratio of an air-fuel mixture that is leaner than the stoichiometric air-fuel ratio in the other cylinder.

Abstract: An ignition apparatus which allows for an accurate diagnosis of a spark plug in an internal combustion engine provided with plural spark plugs for each cylinder is provided for an internal combustion engine. The ignition apparatus is for an internal combustion engine provided with plural spark plugs for each cylinder, and includes an input port which receives fail signals S3 and S4 generated corresponding to each of the plural spark plugs for diagnosis of the spark plugs. An input timing of the fail signal to the input port is made different for each of the plural fail signals. Ignition timings S1, S2 of the plural spark plugs are set to different times.

Abstract: A control device for an internal combustion engine includes a fuel injection device that injects a fuel in accordance with a required injection amount that is required for combustion in a combustion chamber that is performed to produce an output of the internal combustion engine, and a fuel property specific determination device that specifically determines a fuel property of the fuel injected. The control device further includes a control device that performs an output correction process of controlling at least a portion of the internal combustion engine so as to correct the produced output based on a difference in the specifically determined fuel property. According to the control device and a control method thereof, driveability is secured even in the case where a blended fuel is used during a high load region of the internal combustion engine.

Abstract: An ignition apparatus which allows for an accurate diagnosis of a spark plug in an internal combustion engine provided with plural spark plugs for each cylinder is provided for an internal combustion engine. The ignition apparatus is for an internal combustion engine provided with plural spark plugs for each cylinder, and includes an input port which receives fail signals S3 and S4 generated corresponding to each of the plural spark plugs for diagnosis of the spark plugs. An input timing of the fail signal to the input port is made different for each of the plural fail signals. Ignition timings S1, S2 of the plural spark plugs are set to different times.

Abstract: In an exhaust system of an internal combustion engine having a plurality of cylinders, a control valve is disposed downstream of a junction point of one of two exhaust passages of the engine, and a control valve and a catalytic converter are disposed downstream of a junction point of the other of the exhaust passages. The control valves of the two exhaust passages are controlled so that exhaust gas of all of the cylinders mainly passages the catalytic converter of the other exhaust passage during startup of the engine.

Abstract: An object of the present invention is to provide a technique that enables to more preferably suppress an unpreferable exhaust emission in an internal combustion engine having a supercharger while the supercharging pressure is increased by the supercharger. According to the present invention, in an internal combustion engine having a supercharger and an exhaust gas purification catalyst provided in the exhaust passage, while the supercharging pressure is increased by the supercharger, the quantity of the flow-through air that flows from the intake port out into the exhaust port during the valve overlap period is regulated by controlling the valve overlap period (S110, S112) so that the air fuel ratio of the exhaust gas becomes a target air fuel ratio.

Abstract: The invention provides a throttle valve control apparatus of an internal combustion engine having at least a first cylinder group (B1) and a second cylinder group (B2). A first throttle valve (S1) is arranged in an intake passage (31) of the first cylinder group and a second throttle valve (S2) is arranged in an intake passage (32) of the second cylinder group. The throttle valve control apparatus includes a controller that, when there is a demand to switch a combustion air-fuel ratio of the internal combustion engine without changing engine output, first changes an opening amount of the first throttle valve, and then changes an opening amount of the second throttle valve.

Abstract: A first control valve is disposed downstream of a junction point of a first exhaust passage, and a second catalytic converter is disposed downstream of a junction point of the second exhaust passage. The first control valve and the second control valve are controlled so that the exhaust gas of all of the cylinders mainly passes one of the first catalytic converter disposed in the first exhaust passage and the second catalytic converter disposed in the second exhaust passage during a fuel-supply cutoff period.

Abstract: An individual exhaust passage is provided independently for each cylinder group in an internal combustion engine having a plurality of cylinder groups each having a plurality of cylinders. A first catalyst is provided in each of the individual exhaust passages. Downstream of those first catalysts, the individual exhaust passages merge to form a common exhaust passage in which a second catalyst is provided. When control of the internal combustion engine is switched from cylinder group-specific control to stoichiometric control, an air-fuel ratio control portion makes the air-fuel ratio of a cylinder group in which the air-fuel ratio was made rich by cylinder group-specific control lean for a predetermined period of time, and makes the air-fuel ratio of a cylinder group in which the air-fuel ratio was made lean by the cylinder group-specific control rich for a predetermined period of time.

Abstract: A control apparatus for an internal combustion engine includes cylinder internal pressure sensors provided in each cylinder of an engine, and calculates a heat generation quantity in each cylinder based on the detected cylinder internal pressure and a crank angle. The control apparatus then obtains a combustion barycentric position, which is the crank angle at which a predetermined ratio of heat, of the total heat generation quantity in a combustion cycle, is generated. The control apparatus also calculates, based on the heat generation quantity, an actual starting point of combustion, which is a crank angle at which combustion actually started in the cylinder, and obtains the crank angle of the relative combustion barycentric position with respect to the actual starting point of combustion. When this crank angle exceeds an upper limit value, it is determined that combustion has truly deteriorated.

Abstract: In an exhaust purification system that purifies exhaust from a plurality of cylinder groups of an internal combustion engine, an exhaust passageway (1,51) from each cylinder group is divided into a plurality of passageways (2a, 2b, 52a, 52b/3,53). With regard to one or more of the divided exhaust passageways (3,53), the amount of exhaust passing therethrough is reduced so as to reduce the heat release to the outside from the exhaust as a whole. In this manner, the temperature of exhaust introduced into an exhaust purification device (4,54) is kept at high temperature.

Abstract: A dual injection type internal combustion engine including an injector for in-cylinder injection and an injector for intake manifold injection includes a learning device for learning a background noise level based on an output signal of a knock sensor, and a knocking suppression control device for performing, while learning the background noise level, knocking suppression control by controlling fuel injection of the injector for in-cylinder injection or the injector for intake manifold injection. Alternatively, the engine includes a fixing device for fixing, while learning the background noise level, a start timing or end timing of fuel injection by the injector for in-cylinder injection at a basic timing determined by an operating state of the engine.

Abstract: A common fuel injection amount is calculated for the cylinders of a first cylinder group, which performs a rich burn process, and the cylinders of a second cylinder group, which performs a lean burn process. The calculated fuel injection amount is corrected with an air-fuel ratio learning value that is acquired beforehand during a stoichiometric operation. Intake valve lift amounts for the cylinders of the first and second cylinder groups are calculated in accordance with an engine speed and engine load. In compliance with the calculated values, a variable valve mechanism is driven, and fuel is ignited. When performing sulfur poisoning recovery of the Ox catalyst, the exhaust air fuel ratio control means change the intake air amount for each cylinder while providing substantially the same fuel injection amount for all cylinders.

Abstract: A dual injection type internal combustion engine including an injector for in-cylinder injection and an injector for intake manifold injection includes a learning device for learning a background noise level based on an output signal of a knock sensor, and a knocking suppression control device for performing, while learning the background noise level, knocking suppression control by controlling fuel injection of the injector for in-cylinder injection or the injector for intake manifold injection. Alternatively, the engine includes a fixing device for fixing, while learning the background noise level, a start timing or end timing of fuel injection by the injector for in-cylinder injection at a basic timing determined by an operating state of the engine.

Abstract: A common fuel injection amount is calculated for the cylinders of a first cylinder group, which performs a rich burn process, and the cylinders of a second cylinder group, which performs a lean burn process. The calculated fuel injection amount is corrected with an air-fuel ratio learning value that is acquired beforehand during a stoichiometric operation. Intake valve lift amounts for the cylinders of the first and second cylinder groups are calculated in accordance with an engine speed and engine load. In compliance with the calculated values, a variable valve mechanism is driven, and fuel is ignited. When performing sulfur poisoning recovery of the Ox catalyst, the exhaust air fuel ratio control means change the intake air amount for each cylinder while providing substantially the same fuel injection amount for all cylinders.