This disclosure provides system and method that can determine hydraulic start of injection (SOI) in engines using an in-cylinder pressure sensor. The system and method determine apparent heat release rate (AHRR) curve data for the cylinder from the pressure information provided by the in-cylinder pressure sensors, and the hydraulic SOI from the derivative of the AHRR curve data. The system and method provide diagnostic, control and/or compensation opportunities for fuel injector operation in high pressure fuel rail engine systems without use of expensive or complex fuel injector components.

A fuel property diagnostic device configured to diagnose properties of fuel for a vehicle includes a computer configured to diagnose the properties of the fuel for each region based on the number of vehicles with clogging. The number of vehicles with clogging is the number of vehicles in which an internal combustion engine provided with an exhaust gas control device in an exhaust passage is mounted, the exhaust gas control device includes a filter for capturing particulate matter contained in an exhaust gas, and the filter is clogged.

A fuel injection valve drive control device includes a boost circuit having a boost coil, a switching component (FFT or the like) supplying a switching current from a battery source voltage to the boost coil, and a boost capacitor accumulating a boosted voltage generated by the operation of the switching component; a discharge circuit for discharging the accumulated electric charge via a current limiter (e.g. discharge resistor, constant current source) and a discharge switch (FET or the like); and a monitoring circuit for monitoring the accumulated voltage. The discharge circuit is caused to operate when the control device is shutting down and performs a deterioration/failure diagnosis of the boost capacitor and an operation check of the discharge circuit on the basis of a monitored voltage value of the boost capacitor at starting the discharge operation and a monitored voltage value of the boost capacitor after a predetermined time has elapsed.

A method for determining the load status of a filter mounted in a fuel supply system, comprising a fuel supply pump and a control unit for controlling the fuel supply pump, the time curve of the rotational speed of the fuel supply pump being detected over a predetermined period of time, and at least one value of the time curve of the rotational speed and its associated detection time being compared with a comparative value stored in a control unit

An apparatus and method for controlling a fuel injection system of an internal combustion engine is disclosed. Each fuel injector in the system is operated to perform a predetermined injection pattern per engine cycle. A signal representative of a fuel pressure within the fuel rail during the operation of the fuel injectors is sampled. A Fourier analysis of the fuel rail pressure signal is performed to determine one or more harmonic components thereof. The determined harmonic components of the fuel rail pressure signal are used to calculate a dynamic fuel quantity that flows through a fuel injector during an injection pulse of the injection pattern. A fuel quantity actually injected by the fuel injector during the injection pulse as a function of the dynamic fuel quantity is calculated.

Various methods and systems are provided for health assessments of a fuel system. In one example, a method for an inlet metering valve (IMV) includes reducing electrical driving of the IMV, monitoring a response time of the IMV in real-time responsive to the reducing, and determining if the IMV is degraded based on a response of IMV current over a duration, the duration beginning after an initial decrease in current caused by the reducing.

An engine control apparatus is equipped with a fuel injection amount computation unit, a determination process unit, and an engine abnormality process unit. The determination process unit determines, based on a deviation between a command injection amount and a monitoring injection amount, whether or not there is an abnormality in fuel injection control. An injection amount threshold, which is used to make a determination on an abnormality in fuel injection control, is set larger based on a vehicle speed-associated parameter when the vehicle speed-associated parameter is a value corresponding to a case where a vehicle speed is high than when the vehicle speed-associated parameter is a value corresponding to a case where the vehicle speed is low.

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 system includes one or more processors that are configured to obtain a measured fuel consumption rate for an internal combustion engine while the engine is operating at a predetermined operating condition to perform a mission. The one or more processors are also configured to compare the measured fuel consumption rate with an expected fuel consumption rate for the predetermined operating condition. Further, the one or more processors are configured to determine whether an injector flow limiter is in a latched condition based on the measured fuel consumption rate compared with the expected fuel consumption rate. Also, the one or more processors are configured to perform a responsive action responsive to determining that the injector flow limiter is in the latched condition.

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.