An internal combustion engine has a fuel injector that is controlled by an engine control unit. According to one embodiment a device receives from a temperature sensor information corresponding to the temperature of the engine. The device transmits substitute temperature information to the engine control unit when the temperature of the engine is within a predetermined range of temperatures. The substitute temperature information corresponds to a temperature that is different than the actual temperature of the ICE. The engine control unit controls the fuel injector so that it operates in response to the substitute temperature information.

An internal combustion engine includes an upstream side exhaust purification catalyst and a downstream side exhaust purification catalyst. The control device includes a storage amount estimating device which estimates the oxygen storage amount of the downstream side exhaust purification catalyst, and can execute fuel cut control which cuts the feed of fuel to the combustion chamber during operation of the internal combustion engine when the engine speed is the lowest reference speed or more. The control device lowers the lowest reference speed when the storage amount estimated by the storage amount estimating device has become a given limit storage amount or less, compared with when it is larger than the limit storage amount. As a result, a control device can effectively keep the oxygen storage amount of the downstream side exhaust purification catalyst from decreasing to zero.

An air-fuel ratio control device switches a target air-fuel ratio from a lean set air-fuel ratio to a rich set air-fuel ratio after judging that an air-fuel ratio of an outflowing exhaust gas has become a stoichiometric air-fuel ratio and an oxygen storage amount of an exhaust purification catalyst has become a switching reference storage amount, and makes an average value of the target air-fuel ratio the stoichiometric air-fuel ratio to less than the lean set air-fuel ratio, from after the estimated value of the oxygen storage amount has become the switching reference storage amount or more until judging that the air-fuel ratio of the outflowing exhaust gas has become the stoichiometric air-fuel ratio if the estimated value of the oxygen storage amount becomes the switching reference storage amount or more before judging that the air-fuel ratio of the outflowing exhaust gas has become the stoichiometric air-fuel ratio.

Disclosed are: a device for controlling an engine and a hydraulic pump of construction equipment, capable of increasing fuel efficiency by controlling an engine speed and a hydraulic pump discharge flow rate according to the load of a work device; and a control method therefor. The device for controlling the engine and a hydraulic pump of construction equipment, according to the present invention, comprises: a fuel efficiency selection mode means; an engine RPM control means; a hydraulic pump control means; a work device operation sensing means; and a controller having a first control mode such that in the case of selecting the fuel saving mode, the engine RPM is outputted at the RPM lower than that of the general mode while a swash plate swivel angle of the hydraulic pump is increased corresponding to the operation amount of the operation lever, and in the case of the swash plate swivel angle of the hydraulic pump reaching the maximum angle, the engine RPM is increased so as to discharge the flow rate corresponding to the operation amount of the operation lever.

A method for calibrating an electronic fuel injector may include: setting a supply voltage to a control module; applying a control voltage signal having a pulse width to an electronic fuel injector by the control module; determining whether a fuel pressure of a fuel supply to the electronic fuel injector decreases by a predetermined amount; and in response to determining that the fuel pressure of the fuel supply to the electronic fuel injector decreases by the predetermined amount, recording the pulse width and the supply voltage to the control module.

A fuel injection control device controls fuel injection of a spark-ignition internal combustion engine for direct injection into a cylinder and independently controls circulation of a coolant in a head-side cooling channel and in a block-side cooling channel. The fuel injection control device is provided with a controller that sets a fuel injection timing for cooling the inside of the cylinder such that an intake valve closing timing occurs during a reduction in gas temperature inside the cylinder due to evaporative latent heat of the injected fuel, while the coolant circulates in the head-side cooling channel and the circulation of the coolant in the block-side cooling channel is stopped. The controller injects the fuel based on the fuel injection timing for cooling the inside of the cylinder.

A method of controlling a concentration of hydrocarbons in exhaust gas from an internal combustion engine includes sensing an oxygen percentage of the flow of exhaust gas from the internal combustion engine and determining a concentration of hydrocarbons in the flow of exhaust gas. An engine control module may then adjust the sensed oxygen percentage of the exhaust gas based on the determined concentration of hydrocarbons in the flow of exhaust gas to define a corrected oxygen percentage. The control module may then control at least one of a hydrocarbon injection rate for in-cylinder combustion of the internal combustion engine, and a hydrocarbon injection rate for a post combustion exhaust gas treatment process, based on the corrected oxygen percentage, to control the concentration of hydrocarbons in the exhaust gas.

A method for controlling an internal-combustion engine includes detecting knocking in the internal-combustion engine. An EGR gas quantity of EGR gas is increased in a case where the knocking is detected. A part of exhaust gas is circulated into an intake passage as the EGR gas. A fuel octane number of fuel supplied to a cylinder is increased in the case. The fuel octane number is decreased after the fuel octane number has been increased. The EGR gas quantity is maintained so as to prevent the knocking after the EGR gas quantity has been increased.

A cylinder injection valve that injects fuel inside a cylinder and an intake passage injection valve that injects fuel inside an intake passage are provided. When it is determined that deposit greater than or equal to a predetermined amount accumulates, the fuel is forcibly injected by the cylinder injection valve (deposit removing control). The deposit removing control is performed when a pressure of the fuel supplied to the cylinder injection valve is greater than or equal to a predetermined value and an engine load is relatively high. On the other hand, the deposit removing control is not performed when the pressure of the fuel supplied to the cylinder injection valve is greater than or equal to the predetermined value and the engine load is low.

An engine system includes a plurality of injectors disposed at each of one or more combustion chambers of an engine in order to inject a fuel, a plurality of heaters that heat the fuel to be injected from the plurality of injectors, and a controller that determines whether a temperature of external air or a temperature of coolant is less than a predetermined temperature when a starting condition is satisfied, and that operates the plurality of heaters if the temperature of external air or the temperature of coolant is less than the predetermined temperature, wherein the controller compares a heating time that heats fuel with operation of the plurality of heaters with a first predetermined time, and operates the plurality of injectors to inject fuel if the heating time is greater than the first predetermined time.