A fuel injector includes a noise sensor fixed to the body fixed on the injector body to record knocks relevant to the end travel of a control valve and of a needle.

Systems and methods for determining fuel delay in a fuel injected engine with cylinders that may be deactivated are presented. In one example, the fuel injection delay is determined via a cylinder firing schedule array when the cylinder firing schedule array is available. The fuel injection delay is determined via weighted average of a fuel injection delay of a present engine cycle and a fuel injection delay of a past engine cycle when the cylinder firing schedule array is not available.

Methods and systems are provided for reducing errors in estimated fuel rail pressure incurred at the time of a scheduled injection event due to engine-driven cyclic fuel rail pressure changes. In one example, a pulse-width commanded during a scheduled injection event is determined as a function fuel rail pressure samples collected over a moving window that is customized for the corresponding fuel injector. In another example, the commanded pulse-width is determined as a function of an average fuel rail pressure sampled during a quiet zone of injector operation and predicted fuel rail pressure altering events occurring between the quiet zone and the scheduled injection event.

Methods and systems are provided for reducing errors in estimated fuel rail pressure incurred at the time of a scheduled injection event due to engine-driven cyclic fuel rail pressure changes. In one example, a pulse-width commanded during a scheduled injection event is determined as a function fuel rail pressure samples collected over a moving window that is customized for the corresponding fuel injector. In another example, the commanded pulse-width is determined as a function of an average fuel rail pressure sampled during a quiet zone of injector operation and predicted fuel rail pressure altering events occurring between the quiet zone and the scheduled injection event.

The invention relates to a method (100) for operating a solenoid valve (1) for metering a fuel (2) in a fuel injection system (3). The solenoid valve can be actuated against a restoring force (12) by an electromagnet (11), wherein the time curve l(t) of the current I flowing through the electromagnet (11) and/or the time curve U(t) of the voltage U applied to the electromagnet (11) are detected during at least one opening process of the solenoid valve (1). The opening time t.sub.ON and the closing time t.sub.OFF of the solenoid valve (1) are evaluated (110) from the time curve I(t) and/or U(t), and the actual opening duration T.sub.T=t.sub.OFFt.sub.ON of the solenoid valve (1) is compared (140) with a reference value T.sub.R and/or the mass flow dm/dt flowing through the solenoid valve (1) is detected (120) and compared (142) with a reference value M.sub.R during at least one opening process of the solenoid valve (1); and/or a leakage dm/dt of fuel (2) through the solenoid valve (1) is detected (130) in the closed state of the solenoid valve (1). The invention also relates to a corresponding controller (5), a fuel injection system (3), and a computer program product.

A control system for fuel injection by predicting engine noise may include an engine noise predicting device configured to derive a predicted engine noise value in real time by a predicted engine noise coefficient which is pre-stored according to a currently measured combustion pressure value of an engine; and a combustion controller configured to determine a difference between the real-time predicted engine noise value derived by the engine noise predicting device and a target engine noise value for a current operation condition of the engine, and when the engine noise is determined as being degraded due to an abnormal combustion, configured to change the target engine noise value to control fuel injection according to the changed target engine noise value.

A gas engine system controller: calculates a delay calculation value of a knocking occurrence ratio; determines a primary target ignition timing; sets the primary target ignition timing as a current ignition timing if the occurrence ratio difference is positive and an ignition timing does not exceed a converted value of a first advance rate; determines whether a rapid advance condition is satisfied if the occurrence ratio difference is positive and the ignition timing difference exceeds the converted value of the first advance rate; sets a secondary target ignition timing as the current ignition timing if the rapid advance condition is not satisfied, the secondary target ignition timing obtained by adding the converted value of the first advance rate to the previous ignition timing; and determines the current ignition timing so as to achieve a second advance rate greater than the first advance rate if the rapid advance condition is satisfied.

A cavity includes a lower-side cavity, an upper-side cavity, a first lip and a second lip. The upper-side cavity has a guide curved surface which extends along a circumference of a first imaginary circle in a section along a cylinder-axis direction, and the first lip has a curved surface which extends along a circumference of a second imaginary circle in a section along the cylinder-axis direction. An angle X which a cylinder axis makes with a common tangential line of the first imaginary circle and the second imaginary circle is set as 75<X<80. The guide curved surface is configured such that an angle Y of this guide curved surface which occupies at the circumference of the first imaginary circle is set as 80<Y<(180X).

Systems and methods for injecting fuel to an engine in response to a fuel injection delay are presented. The method includes determining fuel delay in a fuel injected engine with cylinders that may be deactivated. In one example, the fuel injection delay is determined via a cylinder firing schedule array when the cylinder firing schedule array is available. The fuel injection delay is determined via a weighted average of a fuel injection delay of a present engine cycle and a fuel injection delay of a past engine cycle when the cylinder firing schedule array is not available.

An injection control device controls a fuel injection valve driven by an electric power. The injection control device includes a current detection unit to detect a driving current supplied to a solenoid of the fuel injection valve, an identification unit to identify a theoretical model of the driving current in a state where a movable core moved by an electromagnetic force generated by the solenoid is at rest, and a state detection unit to detect a state of the movable core. The state detection unit detects the state of the movable core, based on a deviation between the driving current detected by the current detection unit and the theoretical model.