When an EDU determines that a motor is in a control unstable state where the motor cannot be controlled to a target rotation speed due to a drive voltage output duty value being smaller than a threshold value, the EDU performs a control point shifting operation to shift a control point between a first control point, which is in the control unstable state, and a second control point, which is a control stable state outside the control unstable state. Thus, even when the motor is in a stepping rotation state, it is possible to control the target rotation speed regardless of influence of a cogging torque, and appropriately control the cam phase of the intake camshaft to a target phase when the engine is stopped.

A control device for an internal combustion engine is configured to: execute a first decompression operating processing such that a decompression operating state is selected in a first engine speed region that passes in the course of engine stop; execute a decompression stop processing such that a switching from the decompression operating state to a decompression stop state is performed in the course of the engine stop after passage of the first engine speed region; when a temperature correlation value is greater than or equal to a threshold value upon an engine start-up request, execute a second decompression operating processing such that the decompression operating state is selected in a second engine speed region that passes in the course of engine start-up before the start of fuel injection. When the temperature correlation value is smaller than the threshold value, the second decompression operating processing is not executed.

A method according to the invention for controlling an internal combustion engine having a camshaft whose phase with respect to a crankshaft can be adjusted by means of an electric adjustment device, and a control device comprises the steps S1 to S3, wherein in step S1 a stop request is output from the control device to the electric adjustment device. Subsequently, in step S2 a manipulated variable in the form of a pulse duty factor is output from the electric adjustment device, wherein the pulse duty factor counteracts a camshaft torque. In step S3, the direction of rotation of the camshaft is monitored, wherein in step S4, when a reversal of the direction of rotation of the camshaft is detected, an intensity level of this reversal of the direction of rotation is calculated by determining a rotational speed gradient. Furthermore, in a step S5 the pulse duty factor is corrected as a function of the rotational speed gradient in such a way that the influence of the reversal of the direction of rotation on the position of the camshaft is compensated.

Methods and systems are provided for diagnosing a cylinder valve deactivation mechanism in an engine system having cam-actuated valves. Movement of a latch pin of the deactivation mechanism is inferred from an induction current generated by a solenoid coupled to the latch pin, and the inferred movement is used to diagnose operation of cylinder valve deactivation mechanism. The inferred movement and a profile of the induction current is also used to estimate camshaft and crankshaft timing for improved cylinder fuel delivery in the absence of a camshaft sensor.

Provided is a hybrid vehicle that includes a power train including an internal combustion engine equipped with a plurality of cylinders and a drive motor unit. The drive motor unit includes an electric motor coupled to the internal combustion engine without a clutch. The internal combustion engine includes one or more decompression devices that are each installed for a subset of one or more cylinders and that operate to release compression pressure in the subset of one or more cylinders in at least one of the course of an engine stop and course of an engine start-up in which combustion is not performed. The subset of one or more cylinders are selected such that, when the one or more decompression devices are operating, compression is not produced sequentially in cylinders that are adjacent to each other in terms of the firing order.

An apparatus includes a valve and an actuator. The valve has a portion movably disposed within a valve pocket defined by a cylinder head of an engine. The valve is configured to move relative to the cylinder head a distance between a closed position and an opened position. The portion of the valve defines a flow opening that is in fluid communication with a cylinder of an engine when the valve is in the opened position. The actuator is configured to selectively vary the distance between the closed position and the opened position.

Methods and systems are provided for a phase control apparatus in a variable cam timing (VCT) system of an engine, the phase control apparatus having a locked configuration where a locking pin coupled to a first vane of the vane rotor is engaged with a locking pin recess in a cover plate of the phase control apparatus. In one example, the phase control apparatus includes a rubber or plastic isolator pad positioned in a recess in a wall adjacent to the first vane such that when the vane rotor is rotated to the locked configuration, the first vane contacts the isolator pad before it can strike the housing. The isolator pad serves to maintain the gap between the first vane and the housing, and also reduces the likelihood of other vanes of the vane rotor from striking the housing.

Disclosed is a method for determining the state of rotation of a camshaft of a vehicle engine, notable in that the method for determining the state of rotation of the camshaft determines that the state of rotation of the camshaft is in the process of stalling, corresponding to an intermediate state of rotation, when the time elapsed since the last detection of a camshaft wheel tooth-front by the sensor exceeds Tcam_cal, Tcam_cal being defined as the theoretical length of time needed for the camshaft wheel to cover an angular distance equal to the maximum angular distance separating two successive camshaft wheel tooth-fronts at a camshaft rotational speed corresponding to a predetermined low engine speed higher than the minimum engine speed tolerated by the engine.

An apparatus includes a valve and an actuator. The valve has a portion movably disposed within a valve pocket defined by a cylinder head of an engine. The valve is configured to move relative to the cylinder head a distance between a closed position and an opened position. The portion of the valve defines a flow opening that is in fluid communication with a cylinder of an engine when the valve is in the opened position. The actuator is configured to selectively vary the distance between the closed position and the opened position.

In a system that selects a large-cam as a driving cam at a time of a start of an engine, when an engine stop request is output, it is determined whether there is a small-cam cylinder for which a small-cam is selected as the driving cam. In a case where it is determined that there is a small-cam cylinder, a switching command for switching the driving cam from the small-cam to the large-cam is output. When an engine start request is output, the above determination is performed again. In a case where it is determined that there is a small-cam cylinder, the switching command is output to all solenoid actuators again. In addition, the drive of the fuel injector is suspended until the switching operation of the driving cam is completed for all cylinders.