An internal combustion engine control device includes an engine state estimation unit, a wall surface temperature estimation unit, and an operation amount calculation unit. The engine state estimation unit calculates the energy transfer amount from the gas to the wall surface based on the parameter related to the operating condition, the parameter related to the chemical condition of combustion, and the parameter related to an operation status. The wall surface temperature estimation unit estimates the wall surface temperature on the basis of the energy transfer amount from the gas to the wall surface. The operation amount calculation unit calculates an operation amount of an actuator provided in the internal combustion engine on the basis of the wall surface temperature estimated by the wall surface temperature estimation unit.

An internal combustion engine system includes an internal combustion engine including a cylinder, an intake valve and an exhaust valve, a cylinder injection valve, and a variable valve drive mechanism, and a control device that controls the cylinder injection valve and the variable valve drive mechanism. The control device includes a calculation unit that calculates a first crank angle section where a temperature of the cylinder is equal to or higher than a boiling point of the fuel in a compression stroke before completion of warming-up of the internal combustion engine and a second crank angle section where the temperature of the cylinder is equal to or higher than the boiling point of the fuel in the valve closed period, and an injection controller that executes fuel injection in the first and second crank angle sections by the cylinder injection valve.

In an engine including an auxiliary chamber having an ignition plug therein, an amount of heat generated in the auxiliary chamber tends to be large, and thus it is necessary to suppress abnormal combustion. However, when a sensor is added to the ignition plug, a manufacturing cost of the ignition plug tends to increase. An ECU 2 includes an auxiliary chamber temperature estimation unit 21 that estimates a temperature of the auxiliary chamber 42, and an ignition control unit 22 that delays an ignition timing at a first decrease degree defined in accordance with a change amount of the ignition timing with respect to the temperature of the auxiliary combustion chamber as the temperature of the auxiliary chamber 42 increases in a case where the estimated temperature of the auxiliary chamber 42 is included in a middle temperature region equal to or lower than a first set temperature.

In an engine including an auxiliary chamber having an ignition plug therein, an amount of heat generated in the auxiliary chamber tends to be large, and thus it is necessary to suppress abnormal combustion. However, when a sensor is added to the ignition plug, a manufacturing cost of the ignition plug tends to increase. An ECU 2 includes an auxiliary chamber temperature estimation unit 21 that estimates a temperature of the auxiliary chamber 42, and an ignition control unit 22 that delays an ignition timing at a first decrease degree defined in accordance with a change amount of the ignition timing with respect to the temperature of the auxiliary combustion chamber as the temperature of the auxiliary chamber 42 increases in a case where the estimated temperature of the auxiliary chamber 42 is included in a middle temperature region equal to or lower than a first set temperature.

A method for controlling an air-cooled internal combustion engine (ICE) of a motor vehicle controlled by an electronic control unit, includes: activating the electronic control unit; zeroing stored values of temperature of the ICE and the filtered filtering coefficient; in one iteration, —determining whether the ICE is operating, determining a filtering coefficient and a temperature setpoint, —determining a filtered filtering coefficient based on the filtering coefficient and the stored filtered filtering coefficient value, —determining temperature of the ICE according to the coefficient, temperature setpoint and stored temperature of the ICE, —determining whether the ICE is moving and whether the difference between engine temperature and admitted air temperature is below a threshold, ⋅ if not, storing the filtered filtering coefficient and the temperature of the ICE, then beginning a new iteration, and ⋅ if so, transmitting a signal authorizing the shutdown of the electronic control unit.

At least an embodiment may provide a remote server that can predict overheating of an engine. A remote server may receives an engine rotational speed, an engine load factor, and a cooling-water temperature. The remote server calculates a moving average of the engine load factor during a predetermine time, and calculates a correlation between the moving average of the engine load factor and the cooling-water temperature. If the correlation during a predetermined period is in the status of a predetermined difference from the correlation up to the predetermined period, the remote server predicts occurrence of overheating in a swing working vehicle that is used by a user.

A control system includes a processor for controlling an internal combustion engine having a temperature region, wherein a change of ignition delay time accompanying a rise in a cylinder temperature when the cylinder temperature is in the temperature region is smaller than when the cylinder temperature is out of the temperature region. When a self ignition timing of secondary fuel is earlier than a self ignition timing of primary fuel due to the secondary fuel being injected at a crank angle at which the cylinder temperature is higher than the temperature region, the processor controls a ratio of the secondary fuel to be lower than when the self ignition timing of the secondary fuel is later than the self ignition timing of the primary fuel due to the secondary fuel being injected at a crank angle at which the cylinder temperature is within the temperature region.

After an ECU is activated by turning a key switch on, if a total intake air quantity, which is indicative of the engine temperature immediately before turn-off of the key switch, exceeds a set intake air quantity indicative of a full warm-up determination temperature, and a soak time exceeds a set key-off time, it is determined that the condition for executing a diagnosis of a fuel pressure sensor is satisfied.

A system for controlling an engine based on piston temperature deviation includes a piston temperature estimation module that estimates a piston temperature based on engine operating conditions, a piston temperature deviation estimation module that estimates a deviation of the estimated piston temperature from a steady-state piston temperature, and an engine control module that determines an engine control parameter based upon the estimated piston temperature deviation.

An internal combustion engine control device (1) includes an injector-temperature calculation unit (21a), an engine-temperature calculation unit (21b), an operating-state control unit (21c), a cold/warmed-up state determination unit (21d), an ambient-temperature calculation unit (21e), and a correction unit (21f). The correction unit (21f) corrects an engine temperature calculated based on an injector temperature, when it is determined that an engine is in a cold state and a difference between the injector temperature and an ambient temperature is equal to or larger than a first predetermined value.