Various embodiments include a method for operating a fuel injector comprising: applying a first current to a solenoid to perform a first injection process and inject a predefined injection quantity; determining a value of a system parameter indicating the relationship between the actual fuel quantity and the predefined quantity; determining, on the basis of the value of the system parameter, whether the actually injected fuel quantity is smaller than the predefined fuel quantity by a predefined amount corresponding to a disparity between a magnetic force exerted on the armature in the direction of the pole piece and an opposite hydraulic force exerted on the armature by fuel; and if it was determined that the quantities differ by enough, applying a second current to the solenoid to perform a second injection; wherein the second current exerts a lower magnetic force on the armature in the direction of the pole piece.

A method of operating an internal combustion engine of a type that has a combustion chamber, a moveable valve having a seat formed in the combustion chamber, a camshaft on which a cam is mounted, and a rocker arm assembly having a rocker arm and a cam follower configured to engage the cam as the camshaft rotates. The method includes obtaining rocker arm position data, using the rocker arm position data to obtain camshaft position information, and using the camshaft position information in an engine management operation.

Methods and systems are provided for enabling a transfer function of a direct injector and a port injector, each fueling an engine cylinder, to be accurately learned. During selected conditions, the direct injected fuel fraction may be actively changed from a target fraction to one of an upper and lower limit of the direct injector so as to provide a measurable air-fuel ratio error. Fueling errors for the distinct fuel injectors is then learned based on the measured air-fuel ratio error relative to the actively changed fuel fraction.

A method and device for water injection, wherein a water injector (104) is activated in accordance with an activation (200) to open at a first time (t1) and to close at a second time (t2), wherein a water pressure profile (300) is measured and a change in the water pressure profile (400) is determined on the basis of the water pressure profile (300), wherein, depending on the water pressure profile (300) and on the change in the water pressure profile (400), it is determined whether the water injector (104) has been opened as a result of the activation (200), and/or wherein, depending on the water pressure profile (300) and on the change in the water pressure profile (400), it is determined whether the water injection (104) has been closed as a result of the activation (200).

Systems and methods utilize a controller configured to perform a diagnostic routine for a combustion seal provided between a gasoline direct injection (GDI) fuel injector and a combustion chamber of a cylinder of a GDI engine. The diagnostic routine comprises determining one of (i) a period for the injector coil current to reach a peak current and (ii) a resistance of the injector coil while the injector coil current is saturated, determining whether the determined period or the determined injector coil resistance is greater than a respective threshold indicative of a predetermined temperature of the injector coil, and when the determined period or the determined injector coil resistance is greater than its respective threshold, detecting a combustion seal leak fault. Based on the combustion seal leak fault, the controller may modify operation of the engine to prevent potential heat damage to the engine.

Various embodiments may include a method for checking the plausibility of the functionality of a crankcase ventilation system of an internal combustion engine, wherein crankcase ventilation system has a crankcase, an intake tract equipped with an intake manifold, and a connecting line arranged between the crankcase and the intake manifold, the method comprising: detecting an occurrence of a negative load change; in response, comparing a measured intake manifold pressure with a modelled intake manifold pressure using acquired operating variables of the internal combustion engine and of a crankcase model; and determining on the basis of the comparison result whether the connecting line arranged between the crankcase and the intake manifold becomes blocked or drops out.

An internal combustion engine having an exhaust log structure onto which a plurality of turbochargers is connected, each turbocharger having a turbine connected to the exhaust log structure and having an inlet fluidly connectable to a respective one of the plurality of outlet ports, an exhaust valve disposed at a turbine outlet such that the flow of exhaust gas out of the turbine is fluidly blocked, and an actuator associated with the exhaust valve and operating to move the exhaust valve from a closed position to an open position and vice versa. An electronic controller provides a command to the actuator to move the exhaust valve between the open and closed positions and is programmed to selectively open two one or more exhaust valves based on an operating condition of the engine.

Current sensors measure current flowing into and out of an inductive load such as a solenoid coil and provide signals to a processor when the difference between the two measured currents exceeds a threshold. A solenoid coil and electronic devices driving it are protected from damage caused by a short circuit at the connections to the coil.

Methods and systems are provided for drying engine cylinders in situ responsive to engine flooding. In one example, a laser ignition device is operated in each engine cylinder, sequentially, while the cylinder is parked with an intake valve closed and an exhaust valve open. The heat generated by the laser operation vaporizes liquid fuel in the cylinder, which flows out of the cylinder via the open exhaust valve, expediting cylinder drying.

A method for extracting characterizing features from an ion current trace retrieved from spark plugs of cylinders of an internal combustion engine, comprises the steps of: i. dividing the ion current signal into crank angle subintervals; 5 ii. calculating a measure of ion current in each crank angle subinterval; and iii. Performing a calculation on the measure of ion currents from different subintervals such that the result of the calculation is dimension free. Further it relates to a method of monitoring combustion processes where a plurality of ion current signals from a number of spark plugs (4A, 4B) are 10 retrieved and used in combination.