An injection control device includes: a drive control unit that controls energization by correcting an energization instruction time when injecting the fuel by executing the current-drive, and includes an energization time correction amount calculation unit that calculates an energization time correction amount by performing area correction on a current flowing through the fuel injection valve; an abnormality determination unit that determines an abnormality in a control system of the drive control unit; and a correction amount subtraction setting unit that stops a calculation of the energization time correction amount when the abnormality determination unit determines an abnormality, and controls the drive control unit to directly or stepwise reduce the energization time correction amount at an abnormality determination.

An injection control device includes: a boost controller charging a boost capacitor by performing a boost switching control of a boost switch, and supplying a boost power from a battery power source; and a boost voltage monitor monitors a boost voltage. The boost controller measures a number of times of when the boost voltage becomes equal to or higher than a predetermined value due to a boost current flowing into the boost capacitor, causing a jump of the boost voltage during a time between a start and stop of boosting, and determines deterioration of the boost capacitor by comparing the measured number of times (i.e., the number of jumps) with a predetermined number of times.

The disclosure relates to a method for determining a drift in the static fuel flow rate of a piezoelectric injector of a motor vehicle combustion engine. The method relies on fluid-pressure measurements carried out in the injector supply chamber in order to calculate a measured static flow rate value. This value is compared against a nominal static flow rate in order to determine the existence, if any, and amplitude of the drift in the static flow rate. Furthermore, each pressure measurement is carried out when the valve of the injector is closed and the injector is open. In this way, the measured static flow rate calculation is not influenced by pressure-variation effects not relevant to the measurement.

An injection control device includes: a drive control unit that controls energization by correcting an energization instruction time when injecting the fuel by executing the current-drive, and includes an energization time correction amount calculation unit that calculates an energization time correction amount by performing area correction on a current flowing through the fuel injection valve; an abnormality determination unit that determines an abnormality in a control system of the drive control unit; and a correction amount subtraction setting unit that stops a calculation of the energization time correction amount when the abnormality determination unit determines an abnormality, and controls the drive control unit to directly or stepwise reduce the energization time correction amount at an abnormality determination.

An injection control device controls the opening and closing of a fuel injection valve by performing peak current drive and constant current drive with respect to the fuel injection valve and controls injection of fuel from the fuel injection valve to an internal combustion engine. The injection control device includes an energization control unit that performs constant current switching control of an energization current to the fuel injection valve. The energization control unit is configured to, when the energization current to the fuel injection valve is to be stopped, controls an energization stop timing of the energization current such that a flyback period is equal to a first predetermined time period.

The invention is related to a fuel pressure control device for an internal combustion engine, which controls a pressure of fuel supplied to a fuel injection valve and includes: a fuel pump, adopting the internal combustion engine as a driving source, and discharging pressurized fuel to a side of the fuel injection valve; a boost control part, setting a fuel discharge amount of the high-pressure fuel pump to a maximum value for boosting a pressure from a time when cranking starts until a predetermined timing halfway during a startup of the internal combustion engine; and a limit control part, performing limit control which follows the boost control and limits the fuel discharge amount to an upper limit.

An injection control device includes: a boost controller charging a boost capacitor by performing a boost switching control of a boost switch, and supplying a boost power from a battery power source; and a boost voltage monitor monitors a boost voltage. The boost controller measures a number of times of when the boost voltage becomes equal to or higher than a predetermined value due to a boost current flowing into the boost capacitor, causing a jump of the boost voltage during a time between a start and stop of boosting, and determines deterioration of the boost capacitor by comparing the measured number of times (i.e., the number of jumps) with a predetermined number of times.

Disclosed is a method for regulating the output voltage of a DC-to-DC voltage converter of a motor vehicle engine control computer. The method includes a step of the microcontroller simultaneously controlling a control module, so that the control module drives at least one injector of the vehicle engine, and a converter, so that the converter generates its own output voltage by setting the strength of the drive current to its maximum in what is called a “forced” mode corresponding to a step.

The disclosure relates to a method for determining a drift in the static fuel flow rate of a piezoelectric injector of a motor vehicle combustion engine. The method relies on fluid-pressure measurements carried out in the injector supply chamber in order to calculate a measured static flow rate value. This value is compared against a nominal static flow rate in order to determine the existence, if any, and amplitude of the drift in the static flow rate. Furthermore, each pressure measurement is carried out when the valve of the injector is closed and the injector is open. In this way, the measured static flow rate calculation is not influenced by pressure-variation effects not relevant to the measurement.

Systems and methods for improving accuracy of an amount of fuel injected to an engine are disclosed. In one example, a maximum fuel injector holding current value is adjusted from a higher value to a lower value within a predetermined amount of time of an end of fuel injection. By adjusting the maximum fuel injector holding current value, it may be possible to reduce variation in an amount of fuel that is injected via the fuel injector.