A characteristic determining device is provided which determines fuel injection characteristics of a plurality of fuel injectors for an internal combustion engine. The characteristic determining device includes a pressure sensor and a plurality of pipes each of which connects between the pressure sensor and one of the fuel injectors. The pressure sensor is designed to have a plurality of pressure inputs from the respective fuel injectors through the pipes and outputs a signal indicative of a level of pressure in each of the fuel injectors. The characteristic determining device analyzes the signals from the first pressure sensor to determine the fuel injection characteristics of the respective fuel injectors. These arrangements result in a simplified structure of the characteristic determining device and a decreased manufacturing cost thereof.

A method of controlling an engine system includes controlling a fuel injector to perform a zero-fueling injector operation during operation of the engine, the zero-fueling injector operation including a non-zero injector on-time resulting in zero fueling by the injector, determining an injection system pressure change associated with the zero-fueling injector operation, modifying at least one fuel injection control parameter in response to the injection system pressure change, and using the modified fuel injection control parameter to control injection of fuel by the fuel injector during operation of the engine.

The invention relates to a method for testing an electrically activated actuator in a fuel delivery device (10) of an internal combustion engine, wherein the electrical actuator is a controllable valve (15) that is arranged on the inlet side of a high-pressure pump (16). The high-pressure pump (16) conveys fuel into a fuel store (17) having a pressure controller (20). The fuel store (17) is connected to at least one injector (23). The method comprises the following steps: 1) increasing the rotational speed of the high-pressure pump (16), 2) activating the controllable valve (15) until the pressure in the fuel store (17) has reached a first low pressure level, 3) changing the supply of current to the controllable valve (15) by a first specified value such that the controllable valve (15) is opened further and simultaneously maximizing an injection amount by means of the at least one injector (23) until the pressure in the fuel store (17) has reached a first threshold value, 4) activating the controllable valve (15) until the pressure in the fuel store (17) has reached the first low pressure level again, 5) determining a further quantity, which depends on the low pressure level and a maximum value of the pressure that was reached in the fuel store (17).

A method for ascertaining a variable characterizing a flow rate of a fuel injector during an operation of an internal combustion engine, to which the fuel injector is assigned. At least two input values for a data-based model are ascertained, and at least one output value is determined with the aid of the data-based model, on the basis of which a value for the variable characterizing the flow rate of the fuel injector is ascertained. The data-based model combines at least two methods differing from one another for ascertaining a variable characterizing a flow rate of a fuel injector.

A method and system for controlling a fuel pressure valve of a vehicle are disclosed. The disclosed control method includes engine start entrance for controlling a controller to increase an allowable deviation between a current target fuel pressure and an actual fuel pressure when an ignition switch-on signal is received by the controller, fuel pressure determination for controlling the controller to determine whether a deviation value between the target fuel pressure and an actual fuel pressure measured by a sensor is greater than an allowable deviation, and valve control for controlling the controller to determine a duty value for control of opening of the fuel pressure valve, and then controlling the controller to open the fuel pressure valve using the determined duty value, thereby decreasing the actual fuel pressure.

An apparatus and a method for controlling a flow control valve for a high-pressure fuel pump include: a pressure sensor for fuel in a delivery pipe; a control unit for controlling an operation of a flow control valve by controlling a current applied to a coil; a power switching unit for supplying or blocking driving power supplied to the flow control valve based on a control signal of the control unit; and a current adjustment unit electrically connected/disconnected with the flow control valve by the power switching unit to reduce a current supplied to the flow control valve when the current adjustment unit is connected with the flow control valve. Therefore, a noise and a vibration by collision between the plunger and the core upon closing the flow control valve may be attenuated by adjusting a current amount applied to the coil.

A method for testing a high-pressure pump, particularly a high-pressure pump which is provided to inject fuel into a combustion engine, the method including filling the high-pressure pump with a fluid prior to switching it on.

A fuel injector interface device and associated method include an interface device having a plurality of input leads and a plurality of output leads. The input leads are communicatively linked to the fuel pressure sensor on the common rail of a vehicle fuel injection system. The output leads are communicatively linked to a display device such as a diagnostic scope. Circuitry positioned within the interface device detects the rail pressure signals, filters the signals, and outputs data to the display device representing a graphical depiction of the same. A method of using the interface device includes generating the signals, mapping the signals to an individual fuel injector of the vehicle's engine cylinder and determining fluctuations in the strength of the displayed signals to determine anomalies in a particular fuel injector.

A fuel injector test machine is provided such that an injector is fixed on a test feature with a manually operable clamp.

A fuel injector interface device and associated method include an interface device having a plurality of input leads and a plurality of output leads. The input leads are communicatively linked to the fuel pressure sensor on the common rail of a vehicle fuel injection system. The output leads are communicatively linked to a display device such as a diagnostic scope. Circuitry positioned within the interface device detects the rail pressure signals, filters the signals, and outputs data to the display device representing a graphical depiction of the same. A method of using the interface device includes generating the signals, mapping the signals to an individual fuel injector of the vehicle's engine cylinder and determining fluctuations in the strength of the displayed signals to determine anomalies in a particular fuel injector.