An electronic control unit of an internal combustion engine is configured to control the fuel injection valve and to control a spark plug if necessary such that fuel is combusted by pre-mixture compression ignition combustion or flame propagation combustion. The electronic control unit is configured to perform homogeneous combustion in a flame ignition operation range when switching failure has not occurred, the homogeneous combustion being combustion in which fuel homogeneously diffused into the combustion chamber is ignited using the spark plug and is combusted by flame propagation combustion. The electronic control unit is configured to perform spray-guided stratified combustion in a second operation range when the switching failure has occurred, the spray-guided stratified combustion being combustion in which fuel in the fuel injection path is ignited using the spark plug and is combusted by the flame propagation combustion.

Various embodiments include a method for detecting deviations occurring in the valve drive of an internal combustion engine comprising: measuring dynamic pressure oscillations of intake air in an air intake tract of respective internal combustion engine during operation; calculating an inlet valve stroke phase difference and/or an outlet valve stroke phase difference based on the measured dynamic pressure oscillation; calculating a valve stroke phase deviation value with respect to a valve stroke phase reference value based on the calculated phase difference; and calculating a first valve drive deviation value based on the valve stroke phase deviation value.

In the disclosure, an F/B correction coefficient correcting a fuel injection amount so that a detected equivalence ratio detected by an LAF sensor becomes a target equivalence ratio is calculated by using a feedback control containing a predetermined gain, and a reference F/B correction coefficient is further set. By changing a valve overlap characteristic between an intake valve and an exhaust valve in a supercharging state, a scavenging control that scavenges a combustion chamber by blow-by of intake air is executed. During the scavenging control, when the F/B correction coefficient is changing relative to the reference F/B correction coefficient in a direction of further correcting the fuel injection amount to a rich side, the gain of the feedback control is reduced.

Provided is a control device for an internal combustion engine capable of avoiding deterioration of combustion and reliably suppressing synthetic noise of a high pressure fuel pump and a fuel injection valve without affecting an operating state of the internal combustion engine. Therefore, when it is determined that there is synthetic noise of a high pressure fuel pump and a fuel injection valve, an operating angle of a variable valve mechanism provided in the internal combustion engine is made variable while satisfying a fuel injection request of the fuel injection valve.

There is provided an engagement groove (31) which is formed in a first shoe (S1) of first to fourth shoes (S1), (S2), (S3), (S4) at a circumference position at which the engagement groove (31) is not overlapped an abutment surface (30) with a first vane (V1), which includes a pair of side surfaces (31a) and (31a) that are substantially parallel to the abutment surface (30), and with which a positioning pin (19) protruding from a sprocket (13) is engaged, so as to match phases of a housing main body (11) and the sprocket (13) in a rotation direction.

An engine includes a variable valve timing (VVT) mechanism that changes an opening timing or a closing timing of at least one of an intake valve or an exhaust valve in accordance with an operating region of the engine, and an oil jet that injects oil in a piston direction under a pressure of a first predetermined oil pressure or more. The control device of the engine controls supply of an oil pressure to the VVT mechanism in such a manner that an upper limit of an oil pressure used by the VVT mechanism is set to be lower than a first predetermined oil pressure and an operating speed of the VVT mechanism is high in a direction in which an overlap amount between open periods between an intake valve and an exhaust valve increases and is low in a direction in which the overlap amount decreases.

Various embodiments include a method for identifying valve stroke phase differences during operation comprising: measuring dynamic pressure oscillations in the air intake tract; generating a corresponding signal; acquiring a crankshaft phase angle; acquiring the phase position and the amplitude of a signal frequency of the oscillations based on the pressure oscillation using discrete Fourier transformation; acquiring a line of an equal phase position and of equal amplitude of the signal frequency reflecting the inlet and the outlet stroke phase difference using reference lines; acquiring a common intersection point of a line of equal phase position and a line of equal amplitude by projection into a common plane; and determining the stroke phase differences and from the common intersection point.

Various embodiments include a method for identifying an inlet and an outlet valve stroke phase difference comprising: measuring pressure oscillations during operation; generating a corresponding signal; determining a corresponding crankshaft phase angle; applying a discrete Fourier transformation to the pressure signal to determine amplitudes of selected frequencies in relation to the crankshaft phase angle; determining lines of equal amplitudes of the frequencies based on the amplitudes depending on the phase differences using reference lines; determining an intersection of the lines by projection into a common plane; and determining the inlet valve stroke phase difference and the outlet valve stroke phase difference from the determined common intersection point of the lines of equal amplitudes of the selected signal frequencies.

Provided is a control device for an internal combustion engine, which can ensure a stable combustion state of the internal combustion engine even under a high-humidity environment condition, thereby improving the merchantability. The control device for the internal combustion engine includes an ECU (electronic control unit). The ECU calculates a basic target EGR amount according to an operating state of the internal combustion engine, calculates a water vapor amount in air drawn into an intake passage of the internal combustion engine, calculates an EGR conversion amount by using the water vapor amount, calculates a target EGR amount by subtracting the EGR conversion amount from the basic target EGR amount, and controls internal EGR and external EGR of the internal combustion engine by using the target EGR amount.

A method for regenerating an Otto particle filter of an internal combustion engine of a vehicle includes identifying a loading state of the Otto particle filter above a regeneration threshold and operating the internal combustion engine in a heating mode for the purposes of heating the Otto particle filter to a temperature threshold. The method further includes switching a first cylinder of the internal combustion engine from a fuel supply to an air supply, and continuing to operate at least one further cylinder of the internal combustion engine with the fuel supply.