A fuel injection control device and a fuel injection control method for an internal combustion engine according to the present invention correct a basic pulse width by a cylinder-specific correction value that is based on injection variations among fuel injection valves to specify a cylinder-specific pulse width, determine whether or not a split number is acceptable based on a minimum pulse width and a pulse width per one injection calculated from the cylinder-specific pulse width and the split number to modify the split number based on a result of the acceptance determination, modify an acceptance determination reference value which is used in the acceptance determination based on the correction value for each cylinder, and execute split injection based on the split number, the basic pulse width, and the correction value for each cylinder.

A method for detecting a cylinder-specific combustion profile parameter value for an internal combustion engine is described. The method includes the following: (a) detecting a toothed encoder signal, (b) determining a cylinder-specific tooth time interval on the basis of the toothed encoder signal, (c) determining a cylinder-specific phase value on the basis of a Fourier transformation of a part of the toothed encoder signal corresponding to the cylinder-specific tooth time interval, (d) determining the combustion profile parameter value on the basis of the cylinder-specific phase value and a stored transfer function which represents a relationship between the combustion profile parameter and the phase value.

Methods and systems of controlling a dual fuel engine with at least two banks of cylinders are provided. The method may include sensing at least one of temperatures of exhaust from the at least two banks and a pressure of an intake manifold of the at least two banks, and adjusting at least one of a gas flow, a charge flow, or an air flow to one of the at least two banks to balance one of exhaust temperatures of the at least two banks and intake manifold pressures of the at least two banks.

A device for controlling purge of a vehicle includes: a state detector detecting state information to control purge of an engine; a controller generating an amount of fuel of each of cylinders of the engine using an amount of air of each cylinder, compensation information, a lambda control value, and an amount of a purge gas of the engine, checking a purge distribution coefficient according to an amount of an intake air for each cylinder when the state information satisfies a control entry condition, generating an amount of redistribution of the purge gas using the amount of the purge gas and the purge distribution coefficient, and generating an injection time for each cylinder using the amount of fuel, a conversion coefficient, and the amount of redistribution of the purge gas; and an injector injecting fuel in each cylinder during the injection time based on control of the controller.

A control device and a control method for a multi-cylinder internal combustion engine including a post-processing device are provided. The control device includes an electronic control unit executing a temperature raising process of raising the temperature of the post-processing device and a recovery-time process. The temperature raising process includes a stopping process and a rich process. In the stopping process, supply of fuel to several of cylinders is stopped. In the rich process, the air-fuel ratio of an air-fuel mixture for different ones of the cylinders other than the several cylinders is made lower than the stoichiometric air-fuel ratio. In the recovery-time process, the concentration of unburned fuel in exhaust gas discharged to the exhaust passage is made higher than an equivalent concentration, when the temperature raising process is stopped. The equivalent concentration is the concentration of unburned fuel being just enough to react with oxygen in the exhaust gas.

A misfire detection device for an internal combustion engine is configured to execute: a deactivating process that deactivates combustion control for air-fuel mixture in one or some of cylinders; a provisional determination process that uses a detection value of a sensor to output a logical value indicating whether a misfire has occurred; a provisional determination counting process that counts a number of times a specific one of the logical value output by the provisional determination counting process has been output; and an official determination process that makes an official determination of whether the misfire has occurred using, as an input, the number of times counted by the provisional determination counting process during a specific period.

A method for carrying out the operation of an internal combustion engine, wherein liquid fuel injection amounts are injected at cylinders of a group of cylinders of the internal combustion engine in the context of injection events, wherein in a first step, a first cylinder of the group with the strongest knocking tendency over a time period is determined, and in a second step an injection correction occurs such that the injection events at the first determined cylinder can be sequentially reduced in their injection duration or injection amount by a first correction value, while the injection duration or injection amount of the injection events at the other cylinders of the group are sequentially increased by a second correction value.

A method and a device for ascertaining a fluid injection quantity of an injection system. The injection system includes a high-pressure pump, a high-pressure region that adjoins the high-pressure pump, a pressure sensor, and an injector that is fed from the high-pressure region. The method includes detecting a measurement signal using the pressure sensor and segmenting a first pressure profile from the measurement signal. The first pressure profile characterizes the pressure profile prior to a fluid injection using the injector. The method also includes segmenting a second pressure profile from the measurement signal. The second pressure profile characterizes the pressure profile after the fluid injection using the injector. The method also includes performing a core density estimation using the first pressure profile and the second pressure profile, ascertaining a pressure difference, and ascertaining the fluid injection quantity using the pressure difference.

An ECU has a fuel pressure sensor that detects fuel pressure inside of a common rail. The ECU detects the fuel pressure at a predetermined frequency and calculates a drop amount of the fuel pressure in accordance with fuel injection by fuel injectors based on the detected fuel pressure. The ECU acquires a fluctuation amount of a fuel injection amount of each of the fuel injectors based on the drop amount of the fuel pressure and learns an injection characteristic of each of the fuel injectors, the injection characteristic indicating a correlation between the fuel injection amount and the fluctuation amount of the fuel injection. In a case in which a detection timing of the fuel pressure is within a fuel injection period of a predetermined fuel injector, the ECU disallows the learning of the injection characteristic using the fuel pressure detected in the fuel injection period.

In a case where an internal combustion engine is executing an all-cylinder operation to operate all cylinders, an air-fuel ratio estimation part of an ECU 1 estimates an air-fuel ratio of each of the cylinders by using a first observer. On the other hand, in a case where the internal combustion engine is executing a cylinder-cut operation to rest a part of the cylinders and to operate other of the cylinders, the air-fuel ratio estimation part does not estimate the air-fuel ratio of each of the cylinders by using the first observer.