An electronic control unit of a control device for an internal combustion engine executes, for a first cycle, first drive processing for controlling an actuator such that a pin drive operation is executed for switching from a first cam to a second cam, executes second drive processing for controlling the actuator such that the pin drive operation is executed again for a second cycle, and executes abnormality determination processing for determining that a cam switching mechanism has an abnormality in a case where a pin returns to a reference position by using a pin return section following a cam switching section of the first cycle after the execution of the first drive processing and the pin returns to the reference position by using the pin return section following the cam switching section of the second cycle after the execution of-the second drive processing.

A linear variable differential transformer (LVDT) for monitoring engine valve position is disclosed. The system includes a valve guide having an elongated recess through it. The engine valve has a valve head and a valve stem with two adjacent materials having different magnetic properties meeting at an interface. The valve stem fits and moves linearly within the valve guide, and the valve head closes an engine combustion chamber. It also includes monitoring coils within the valve guide that create a signal related to the position of the interface within the valve guide. An engine control unit (ECU) is coupled to the monitoring coils and receives and analyzes the signal from the monitoring coils to determine operation of the valve.

A switching roller finger follower for valve actuation comprises a pair of outer arms comprising an axle mounting. A bridge portion joins the pair of outer arms. A latch assembly comprises a ferrule. The ferrule is configured to reciprocate in a latch recess. An inner arm is pivotably mounted to a main axle and comprises a bearing rotatably mounted to a bearing axle. The bearing is configured to transfer forces from a cam lobe to the inner arm. A catch on the inner arm is configured to latch against the lip when the ferrule is in a first position. The catch can pivot past the ferrule when the ferrule is in a second position.

Intake holes at the opposite ends are opened and closed by first intake valves. The middle intake hole is opened and closed by a second intake valve. A control device includes an intake variable valve device. First branch channels are connected to the intake holes and produce a normal tumble flow. A second branch channel is configured such that the flow rate of intake air passing through the middle intake hole is relatively greater on the side closer to the outer periphery of the combustion chamber. Where increasing the flow coefficient is given a higher priority, a three-valve drive mode is selected. Where the strength of the normal tumble flow is enhanced, a two-valve drive mode is selected. Where production of the normal tumble flow is reduced, a one-valve drive mode is selected.

A method for a knock control for an internal combustion engine with at least one cylinder, which is assigned to at least one intake valve, when knocking occurs in at least one cylinder by actuation of the intake valve associated with the cylinder detected as knocking, in such a way that the temperature of the charge of the cylinder detected as knocking is reduced, the knocking in the cylinder is reduced, on actuating the intake valve associated with the cylinder detected as knocking, a cylinder-specific and/or a global measure for power compensation of the internal combustion engine is performed.

An operating range boundary for switching a cam for driving an intake valve (drive cam) is changed in a direction of increasing an engine load if a target EGR rate is predicted to increase across the contour line shown in FIG. 3 during an acceleration operation. As can be seen from comparing FIG. 6 and FIG. 7, a switching boundary in FIG. 7 is changed in a higher load direction than that in FIG. 6. By changing to such a high load direction, a range in which a large cam is selected is enlarged. That is, switching of the drive cam from the large cam to a small cam is delayed. Therefore, it is possible to suppress deterioration of the combustion state in the cylinder.

A variable-lift valve train for a gas exchange valve of an internal combustion engine includes a lift adjuster, a lift actuator, and a lift lever. The lift adjuster has a working curve that is arrangeable at least in a first working position for setting a partial lift and in a second working position for setting a maximum lift. The working curve has a lift region and a base circle region. The lift actuator, which has an actuating contour configured to deflect the lift adjuster. The lift lever, which is deflectable via the working curve and thereby actuates a lift of the gas exchange valve. The valve train is configured to, in the first working position and in the second working position, actuate the gas exchange valve with an at least substantially equal maximum valve acceleration.

A hybrid vehicle includes a controller that executes catalyst warm-up control for warming up a catalyst, including first control that operates an internal combustion engine at a first operating point, and second control, after executing the first control, that operates the engine at a second operating point irrespective of driving force required to propel the vehicle. Engine output at the second point is larger than engine output at the first point. Ignition timing of the engine at the time when the first control is executed is controlled to a retarded side with respect to an ignition timing of the engine at the time when the second control is executed. When the second control is executed, at least one of a valve lift of an intake valve and a valve operating angle of the intake valve increases as charging of an electrical storage device is more limited.

A controller of a hybrid vehicle is configured to operate the internal combustion engine with ignition timing of the internal combustion engine during the execution of the first warm-up control for operating the internal combustion engine at a first operating point further on a retard side than ignition timing of the internal combustion engine during the execution of the second warm-up control for operating the internal combustion engine at a second operating point, regardless of the driving force required for traveling after the execution of the first warm up control. The controller is configured to set the output of the internal combustion engine and the operation characteristic of the intake valve in accordance with a predetermined characteristic relationship in which the output of the internal combustion engine and the operation characteristic of the intake valve correspond to each other during the execution of the second warm-up control.

A method for diagnosing a variable-lift camshaft follower of an internal combustion includes detecting a first knock using a spark knock sensor of the internal combustion engine; retarding ignition timing of the internal combustion engine after detecting the first knock such that the ignition timing is retarded sufficiently to ensure that spark knock is no longer possible; detecting a second knock using the spark knock sensor after retarding the ignition timing sufficiently to ensure that spark knock is no longer possible; determining that the variable-lift camshaft follower is not functioning as desired based on the second knock; and activating a malfunction alert based on the determining that the variable-lift camshaft follower is not functioning as desired.