A control method can be used for securing continuously variable valve duration (CVVD) startability when a CVVD error is recognized by a CVVD controller during an operation of a CVVD system. The control method includes performing engine startability securing control for solving the CVVD error by applying a starting air volume to starting of an engine through at least one of a valve position fixing value, a valve position threshold, or an immediately previous valve position value.

A valve timing adjustment device having a phase adjustment unit including an input rotator, a driving rotator that rotates in conjunction with a crankshaft, a driven rotator that rotates in conjunction with a camshaft that changes a relative rotation phase between the driving rotator and the driven rotator. A controller is configured to perform a startup phase control when operation of the internal combustion engine is started, the startup phase control including setting the relative rotation phase to a predetermined initial phase, and perform a startup preparation control during a period after the internal combustion engine is stopped and before the startup phase control is performed, the startup preparation control including changing the relative rotation phase.

An adjusting unit of an internal combustion engine is provided, comprising an electric motor and a transmission interacting therewith, an adjusting shaft of the transmission being coupled to the rotor of the electric motor. A drive shafts of the transmission is coupled to the shaft which is to be adjusted. For controlling the electric motor, a sensorless control unit is provided outside of a housing of the electric motor which encloses the stator of the electric motor.

An electronic phaser system configured for use in an engine system is provided. The electronic phaser system comprises an intake camshaft, an electronic phaser and an engine control module (ECM). The intake camshaft has a plurality of camshaft lobes. The electronic phaser couples a gearbox to the intake camshaft. The electronic phaser is configured to rotationally advance the intake camshaft an amount of crank degrees to a desired rotational position. The ECM targets a desired cranking compression ratio based on one of an engine stop request and an engine start request. The ECM converts the desired cranking compression ratio into a camshaft lobe centerline position and commands the electronic phaser to rotate the intake camshaft to the desired rotational position that satisfies the camshaft lobe centerline position to achieve the desired cranking compression ratio. The desired cranking compression ratio is between 5:1 and 6:1.

A system includes a valve actuation system, a pre-lubrication pump coupled to a lubrication circuit and configured to provide oil to the valve actuation system, a catalyst for receiving and treating exhaust gasses, and a controller. The controller is configured to identify an engine start request and determine whether the catalyst temperature is below a first threshold value. In response to determining that the catalyst temperature is below the first threshold value, the controller actuates the pre-lubrication pump to direct lubricant to the valve actuation system, controls the valve actuation system to deactivate at least one cylinder of an engine, and, subsequent to deactivating the at least one cylinder of the engine, cranks the engine.

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 for diagnosing an engine system including a continuous variable valve duration (CVVD) apparatus, a driving unit of the CVVD apparatus including a first driving unit and a second driving unit, a CVVD position detector configured to detect a position of the CVVD apparatus, a camshaft position detector configured to detect a position of a camshaft, a front lambda detector configured to detect a lambda value at front of intake valve, and a controller may include the steps of starting the engine, detecting measured values of the front lambda detector during combustion of first to fourth cylinders (first to fourth lambda values), determining whether CVVD driving unit is misaligned according to the detected first to fourth lambda values, and generating a warning notification when the CVVD driving unit is determined to be misaligned.

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.

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.