The engine controller includes storage which stores a fuel efficiency operation line for optimizing engine fuel consumption and a booming noise avoidance operation line for keeping the booming noise below a certain limit. The operation point region where the booming noise exceeding the certain limit is generated is a booming noise region. The fuel efficiency operation line passes through the booming noise region. In contrast, the booming noise avoidance operation line does not pass through the booming noise region. The controller controls the engine according to the booming noise avoidance operation line. The controller controls the engine according to the fuel efficiency operation line for a predetermined period after determining that the driver intends to change the speed of the vehicle.

A method of engine electrical load shed control includes receiving an accessory load indicator corresponding to an accessory load of an engine. A request for acceleration of the engine is detected. One or more electrical buses are depowered based on the accessory load indicator exceeding a shedding threshold and detection of the request for acceleration of the engine.

An abnormality detection device is mounted on an engine control device that calculates a target load factor by using a target torque, converts the target load factor to a target throttle opening, calculates a target ignition timing by using a target efficiency, and controls an engine based on the target throttle opening and the target ignition timing. In the abnormality detection device, a target efficiency for monitoring is calculated by using the target ignition timing, a target torque for monitoring is calculated by using the target efficiency for monitoring and the target load factor, a torque deviation between the target torque for monitoring and the target torque is calculated, and the presence or absence of an abnormality is detected by using the torque deviation.

Various embodiments of the present disclosure are directed towards free-piston combustion engines. As described herein, a method and system are provided for displacing a free-piston assembly to achieve a desired engine performance by repeatedly determining position-force trajectories over the course of a propagation path and effecting the displacement of the free-piston assembly based, at least in part, on the position-force trajectory. In a dual-piston assembly free-piston engine, synchronization of the two piston assemblies is provided.

Methods and systems are provided for learning fuel injector error for cylinder groups during a deceleration fuel shut-off (DFSO), where all cylinders of an engine are deactivated, sequentially firing each cylinder of a cylinder group, each cylinder fueled via consecutive first and second fuel pulses of differing fuel pulse width from an injector. Based on a lambda deviation between the first and second pulses, a fuel error for the injector and an air-fuel ratio imbalance for each cylinder is learned. Alternatively or additionally, a difference in crankshaft acceleration between the first and second pulses relative to the expected deviation may be used to learn torque error, and adjust fuel injector error and air-ratio imbalance for each cylinder.

Methods and systems are provided for improving vehicle torque control accuracy. Data points of an engine torque data set are adjusted en masse by an on-board vehicle controller while also being adjusted individually by an off-board controller. By adjusting engine operation based on a torque data set that is updated by each of the on-board and off-board controllers, engine torque errors can be reliably determined and compensated for.

To provide a controller for internal combustion engine which can suppress deterioration of the detection accuracy of the combustion state due to influence of the external disturbance component, when detecting a combustion state based on angle detection information by the crank angle sensor. A controller for internal combustion engine calculates a shaft torque in unburning; calculates an external load torque based on the shaft torque in unburning and the actual shaft torque in the vicinity of the top dead center; and in an integration crank angle interval which is set corresponding to a combustion period, calculates a subtraction value by subtracting the external load torque from the shaft torque in unburning, calculates a division value by dividing the subtraction value by the inertia moment, and calculates a combustion state index by integrating a value obtained by subtracting the division value from the crank angle acceleration.

To provide a controller for internal combustion engine which can suppress deterioration of the detection accuracy of the combustion state due to influence of the external disturbance component, when detecting the combustion state based on angle detection information by the crank angle sensor. A controller for internal combustion engine calculates a shaft torque in unburning; calculates an external load torque based on the shaft torque in unburning and the actual shaft torque in the vicinity of the top dead center; and in an integration crank angle interval which is set in the compression stroke and the combustion stroke, calculates a subtraction value by subtracting the external load torque from the shaft torque in unburning, calculates a division value by dividing the subtraction value by the inertia moment, and calculates a combustion state index by integrating a value obtained by subtracting the division value from the crank angle acceleration.

A normal control unit performs a normal control to cause an injection apparatus to perform predetermined normal injection and subsequently cause an ignition plug to perform ignition. In a delay region in a combustion chamber, propagation of flame is retarded further than in another region when the normal control is performed. In a knock state, self-ignition occurs in the delay region when the normal control is performed. When the knock state is established, an adjustment control unit performs, to suppress the self-ignition, an adjustment control to perform main injection and subsequently perform sub-injection in a second half of a compression stroke to adjust a fuel distribution in the combustion chamber to facilitate propagation of flame to the delay region further than in the normal control and subsequently cause the ignition plug to perform the ignition.

A misfire determination period is set to a predetermined range of a crank angle. A CPU performs: a calculation process of calculating an average value of a torque of an output shaft of an internal combustion engine in the misfire determination period; a misfire determining process of determining that a misfire has occurred when the calculated average value is less than a prescribed threshold value; and a process of setting the whole misfire determination period to a period in a positive torque range which is a range of a crank angle at which the torque of the output shaft is equal to or greater than zero at the time of normal combustion in which a misfire does not occur.