An individual cylinder air-fuel ratio estimation of estimating an air-fuel ratio of an individual cylinder is performed on a sensed value of an air-fuel ratio sensor set in an exhaust gas collection part of an engine, and an individual cylinder air-fuel ratio control of controlling the air-fuel ratio of the individual cylinder is performed in such a way that a variation in the air-fuel ratio between the cylinders becomes small on the basis of an estimated air-fuel ratio of the individual cylinder. Further, it is determined whether or not a misfire of the engine is caused and when it is determined that the misfire of the engine is caused, the individual cylinder air-fuel ratio estimation and the individual cylinder air-fuel ratio control are stopped and an individual cylinder correction value by the individual cylinder air-fuel ratio control is reset. In this way, it is possible to avoid the individual cylinder air-fuel ratio control from being performed continuously as usual in a state where the air-fuel ratio of the individual cylinder cannot be controlled correctly due to the effect of the misfire.

Systems, methods and apparatus for controlling operation of dual fuel engines are disclosed that regulate the fuelling amounts provided by a first fuel and a second fuel during operation of the engine. The first fuel can be a liquid fuel and the second fuel can be a gaseous fuel. The fuelling amounts are controlled to improve operational outcomes of the duel fuel engine.

The method for controlling valve timing of an engine includes: classifying control regions; applying a maximum duration to an intake valve and a long duration to an exhaust valve in a first control region; advancing Intake Valve Closing timing, applying the long duration to the exhaust valve, and maintaining a maximum valve overlap in a second control region; applying the long duration to the exhaust valve and advancing the IVC timing and Exhaust Valve Closing timing in a third control region; applying a short duration to the exhaust valve and controlling the EVC timing in a fourth control region; controlling a throttle valve, applying the short duration to the exhaust valve, and retarding Exhaust Valve Opening timing in a fifth control region; and controlling the throttle valve and the EVC timing, applying the long duration to the exhaust valve, advancing the EVO timing in a sixth control region.

Systems and methods are for controlling internal combustion engines having a plurality of piston-cylinders that cause rotation of a crankshaft. A crankshaft sensor is configured to sense rotational speed of the crankshaft. A controller is configured to calculate an an engine speed increase for each piston-cylinder based upon the rotational speed of the crankshaft and then balance the engine speed increases of the respective piston-cylinders by modifying a combustion input to one or more of the piston-cylinders in order to reduce engine vibration.

A control apparatus for an internal combustion engine is provided to calculate, on the basis of the output values of the in-cylinder pressure sensor, a combustion index value which indicates the stability of combustion. If reduction of knock is required, the spark timing is retarded. An increment of injected fuel is executed in such a manner that a combustion index value that indicates the actual stability of combustion at a retard execution cycle that is a combustion cycle at which the retard of the spark timing is executed approaches a target value of a combustion index value that indicates the stability of combustion at a before-retard cycle.

A control device includes an electronic control unit. The electronic control unit is configured to calculate an ignitionability index value and a combustion timing index value. The electronic control unit is configured to store relevant information defining a relationship between the ignitionability index value and the combustion timing index value, and a torque fluctuation limit value. The electronic control unit is configured to calculate a distance between a current operating point, which is specified by the ignitionability index value and the combustion timing index value, and a point on the torque fluctuation limit line. The electronic control unit is configured to retard ignition timing when the distance is larger than a threshold value, and enrich an air-fuel ratio and retard the ignition timing when the distance is equal to or smaller than the threshold value.

At least some embodiments of the present disclosure are directed to systems and methods for controlling a cylinder deactivation (CDA) operation for an electrified powertrain, the electrified powertrain comprising an engine and an additional power source, the engine having a plurality of cylinders. The method includes the step of: operating the electrified powertrain in a CDA mode and deactivating one or more selected cylinders of the plurality of cylinders; receiving measurement data indicative of operating conditions of the electrified powertrain; analyzing the measurement data to determine whether a predetermined operating condition is met; and adjusting the CDA operation by adjusting the duration of the CDA operation or changing a number of deactivated cylinders.

A vehicle control device controls a vehicle including an internal combustion engine, an electric motor, a drive wheel, and a lock-up clutch provided in a power transmission path from the internal combustion engine and the electric motor to the drive wheel. The vehicle control device is configured to: not execute a motor vibration damping control and a slip vibration damping control in a non-vibration damping region; execute the motor vibration damping control and the slip vibration damping control in a first vibration damping region in a high load state or a low rotation speed state; and execute the motor vibration damping control and not execute the slip vibration damping control in a second vibration damping region in a medium load state or a medium rotation speed state.

The control device for an internal combustion engine disclosed in the present application is a control device that determines the presence or absence of misfire based on an angle detection cycle calculated from an output signal of an angle sensor, the control device includes an arithmetic processing device and a storage device, the control device is configured so that the storage device stores the angle detection cycle calculated in a misfire detection threshold value comparison section after the reference angle section as a threshold value comparison target cycle and is configured such that the arithmetic processing device determines the presence or absence of misfire based on the misfire detection threshold value cycle calculated based on the reference detection cycle and the threshold value comparison target cycle, thereby it becomes possible to accurately determine the presence or absence of misfire in the control device for the internal combustion engine.

A misfire detecting system for an engine of a vehicle that detects a misfire of the engine is provided, which includes a processor. The processor determines whether a misfire has occurred by examining whether a fluctuation of a crank angle of the engine is equal to or greater than a determination reference value, acquires a value relating to a density of intake air introduced into the engine, and adjusts the determination reference value according to the value related to the density.