Some examples described herein may involve determining an advance timing window between the valve opening or closing and a designated time that the valve is scheduled to open or close; determining a closing velocity of the valve; monitoring an engine speed of the engine; determining valve lash information based on the advance timing window, the closing velocity, and the engine speed, wherein the valve lash information identifies a magnitude of the valve lash or whether the magnitude of the valve lash associated with the valve satisfies a threshold; and performing an action based on the valve lash information.

A method is described to control an actuation profile of an electromechanical linear actuator device of an internal combustion engine designed to control the movement of a component; the internal combustion engine comprises a sensor, which faces the actuator device and is designed to detect the noise generated by the movement of the component; the method comprises the steps of acquiring, by means of the sensor, the intensity of a signal generated by the impact of the component against a limit stop; identifying a first listening window of the signal associated with said impact; calculating a noise index inside the listening window; comparing the noise index with a reference value; and controlling the actuation profile of the actuator device based on this comparison.

A method for diagnosing a waste gate valve malfunction in a power generation system is presented. The method includes determining an actual pressure differential across a throttle valve. The method further includes determining an estimated pressure differential across the throttle valve based on one or more first operating parameters of the power generation system. Furthermore, the method includes determining an absolute difference between the actual pressure differential and the estimated pressure differential. Moreover, the method also includes comparing the absolute difference with a threshold value and if the absolute difference is greater than the threshold value, determining an operating condition of the throttle valve. Additionally, the method includes determining whether the waste gate valve has malfunctioned based on the determined operating condition of the throttle valve. An engine controller and a power generation system employing the method are also presented.

An engine control apparatus and method in which when an injector malfunction is determined based on a difference in variation of angular velocity of a crankshaft between a plurality of cylinders of a vehicle engine, determining whether the injector malfunctions by avoiding the time when the driving torque of an air compressor is applied or at the time when the influence thereof is reduced, thereby preventing the erroneous determination of whether the injector malfunctions from occurring due to the driving torque of the air compressor connected to the vehicle engine.

An internal combustion engine includes a cam-actuated rocker arm assembly with a solenoid-actuated latch that provides for cylinder deactivation or variable valve actuation. The solenoid is in a position where its inductance varies significantly in relation to the position of a latch pin as it translates between latching and non-latching configurations. A sensor is positioned to monitor a current or a voltage in a circuit that includes the solenoid. The sensor data is analyzed to provide diagnostic information relating to the operation of the rocker arm assembly.

Various embodiments include a method for operating an internal combustion engine comprising: determining a torque output of each cylinder resulting from a fuel injection; determining a difference in the respective torque output; comparing the difference with a predetermined threshold; determining a respective injection mass; determining a difference in the respective injection masses; comparing the difference with a threshold; if the differences exceed the threshold, determining whether the respective torque outputs correspond to the associated injection mass; and if the respective torque outputs lie outside a predetermined tolerance range for a respective corresponding injection mass, changing an injection time in at least one of the at least two cylinders.

A valve control device controls a valve drive mechanism on the basis of a degree-of-opening signal for a valve and a startup signal for an engine, and includes: a drive signal generating unit that, when it is determined on the basis of the startup signal that the engine is stated, generates a test drive signal for test-driving the valve before the generation of a normal drive signal associated with normal driving of the valve; and an abnormality determining unit that, on the basis of the degree-of-opening signal during the test driving, determines whether or not an abnormality has occurred in the drive mechanism. The drive signal generating unit stops generating the test drive signal and the normal drive signal when the abnormality determining unit determines that the abnormality has occurred in the drive mechanism.

Systems and methods for diagnosing the presence or absence of turbocharger wastegate degradation are presented. In one example, an intake manifold pressure sensor provides a basis for determining whether or not turbocharger wastegate degradation present. The turbocharged engine may be rotated in a reverse direction to assess wastegate degradation.

Methods and systems are provided for diagnostics of a wastegate valve during vehicle-off conditions. In one example, the engine may be reverse rotated, unfueled, and air flow via the intake manifold may be estimated and compared to a baseline air flow. A stuck open wastegate valve may be indicated based on the comparison between the intake air flow and the baseline air flow.

A method for monitoring leakage of an exhaust gas recirculation system for an engine of a vehicle includes: determining, by a controller, whether the engine is in an idle state in which the exhaust gas recirculation system is not operated; determining, by the controller, whether small flow leakage of the exhaust gas recirculation system occurs based on a predicted pressure of gas sucked into an intake manifold connected to the engine and a measured pressure of gas sucked into the intake manifold when the engine is in the idle state; and determining, by the controller, that leakage of the exhaust gas recirculation system occurs when the measured pressure is greater than the predicted pressure.