Systems, devices and methods for diagnosing malfunctioning in a crankcase ventilation (CCV) system are provided. A controller includes a processor and a memory storing instructions that cause the processor to: receive a plurality of pressure values including (i) a first pressure value indicative of a pressure of fluid flowing from a crankcase to a breather assembly of a system, (ii) a second pressure value indicative of a pressure of fluid flowing through a first tube coupled to the breather assembly, and (iii) a third pressure value indicative of a pressure of fluid flowing through a second tube coupled to the breather assembly; determine a pair of pressure differences based on the first pressure value, the second pressure value, and the third pressure value; and detect a malfunctioning in the CCV system based on the pair of pressure differences.

Systems and methods regarding a ducted fuel injection (DFI) combustion system for an internal combustion engine can control an injection timing of a fuel injector to output fuel injections through at least one duct and into a combustion chamber of the internal combustion engine. The injection timing can include one or more pilot injections according to a predetermined range before top dead center (BTDC) for a combustion cycle; and a main injection into the combustion chamber for the combustion cycle after all of the one or more pilot injections. A first amount of the fuel injected for the main injection can be greater than a second amount of fuel injected for the one or more pilot injections. The predetermined range before top dead center (BTDC) of the one or more pilot injections can be from 85 to 40 degrees BTDC.

A control system of an electronic-controlled oil-gas dual fuel engine includes electronic control pumps, fuel gas injection electromagnetic valves, a fuel gas control device and a fuel oil control device. The fuel gas control device and the fuel oil control device are electrically connected with a control device of the engine. The fuel gas control device is electrically connected with the fuel gas injection electromagnetic valves and controls the opening time and the opening duration of each fuel gas injection electromagnetic valve installed on a pipeline between a natural gas rail and a cylinder cover air inlet channel of the engine. The fuel oil control device is electrically connected with the electronic control pumps, and controls the starting time and the operation duration of the electronic control pump, and the electronic control pumps are installed on a pipeline between an engine fuel oil rail and a cylinder cover fuel injector.

An engine system is provided, which includes a vehicle-mounted engine having an injector, a spark plug, and a property adjusting device, an accelerator opening sensor, and a controller. The controller performs a combustion control for controlling the injector, the spark plug, and the property adjusting device so that a target torque set based on a present accelerator opening detected by the accelerator opening sensor is outputted in a specific cycle in the future from a present time by a given delay time. In the combustion control, the controller sets a target load of the engine in the specific cycle based on the present accelerator opening, and sets a combustion transition from the present cycle to the specific cycle by selecting beforehand combustion from the present cycle to the specific cycle, from flame propagation combustion and compressed self-ignition combustion, based on the set target load.

An engine system is provided, which includes a vehicle-mounted engine having an injector, a spark plug, an intake valve operating mechanism, and an exhaust valve operating mechanism, an accelerator opening sensor, and a controller. The controller sets beforehand a combustion mode so that a target torque set based on an accelerator opening is realized in a specific cycle in the future from a present time by a given delay time, sets an in-cylinder property when an intake valve is closed in the specific cycle so that the set combustion mode is realized in the specific cycle, estimates the actual in-cylinder property when the intake valve is closed in the specific cycle, when the delay time passes and the cycle becomes the specific cycle, and adjusts an operating amount of at least one of the injector and the spark plug, when the estimated in-cylinder property deviates from the target in-cylinder property.

Systems and methods are provided for diagnosing cylinders in an engine. In one example, the method may include selecting a cylinder of the engine for perturbation, and while maintaining a horsepower output of the engine, perturbing the cylinder. Responsive to the perturbation of the cylinder inducing a crankcase pressure difference greater than or equal to a threshold difference, a degradation condition of the cylinder may be indicated. In one example, the perturbation may include cutting fuel to the cylinder. In one example, an engine load may be redistributed among each of remaining cylinder of a plurality of cylinders of the engine to maintain the horsepower output of the engine.

When a diesel engine is determined to be in a motoring state, a hysteresis zero angle H.sub.0 is determined (step S14). Subsequently, a gradient d.sub.n is calculated (step S16). The gradient d.sub.n is calculated based on data (θ.sub.n, Δh.sub.n) of a deviation Δh.sub.n at a retardation side from the hysteresis zero angle H.sub.0 and at an advance side from a predetermined crank angle. Subsequently, the gradient d.sub.n and the hysteresis zero angle H.sub.0 are updated (step S18). When the diesel engine is determined to be in a non-motoring state, data (θ.sub.n, P.sub.n) of an actual in-cylinder pressure is corrected based on a newest correction coefficient η and hysteresis zero angle H.sub.0 (step S22).

The disclosure concerns an internal combustion engine comprising an exhaust camshaft, an intake camshaft, a turbocharger, and a control system. The turbocharger comprises a compressor. A timing of the exhaust camshaft and a timing of the intake camshaft are controllable by the control system, which is configured to: store a compressor map related to the compressor, store a reference area within the compressor map, and determine at least two parameters. In response to the at least two parameters indicating that a current operational point of the compressor is outside the reference area, the control system changes the timing of the exhaust camshaft to advance closing of the exhaust valve, and the timing of the intake camshaft to delay opening of the intake valve.

To provide a controller for internal combustion engine which can improve the estimation accuracy of the period in the chipped tooth section, even if the period is suddenly varied in the chipped tooth section. A controller for internal combustion engine detects a period when the tooth passes, based on an output signal of the crank angle sensor; determines a period corresponding to the chipped tooth section; determines a crank angle corresponding to the passed tooth; and estimates a period of a virtual unit angle interval when assuming that the tooth is provided at the unit angle interval in the chipped tooth section, based on the period of the chipped tooth section, the period before the chipped tooth section, and the period after the chipped tooth section.

A control device for an internal combustion engine is provided. The internal combustion engine includes a cylinder, an in-cylinder pressure sensor, a fuel injection valve, and an alcohol concentration sensor. The control device includes an electronic control unit. The electronic control unit is configured to: carry out learning of fuel properties with the fuel injected from the fuel injection valve as a target; calculate a combustion speed parameter, showing a combustion speed, within the cylinder, of the fuel that is a learning target of the fuel properties, on a basis of the in-cylinder pressure; and determine that water is included in the fuel when the capacitance of the fuel detected by the alcohol concentration sensor is larger than a preset first threshold, and when the combustion speed of the fuel within the cylinder is smaller than a preset second threshold.