A control device is included in a fuel injection system. The fuel injection system includes a low pressure pump, a high pressure pump, an accumulator, a fuel injection valve, a relief valve, and a return pipe. The high pressure pump increases a pressure of a fuel discharged from the low pressure pump and discharges high pressure fuel. The accumulator stores the high pressure fuel discharged from the high pressure pump. The relief valve is provided in a high pressure portion provided downstream from the high pressure pump and opens when a high pressure abnormality occurs in the high pressure portion. The return pipe returns the high pressure fuel in the high pressure portion to a low pressure portion provided downstream from the low pressure pump by the relief valve opening.

Systems and methods are provided for determining and correcting air/fuel imbalance between cylinders of an internal combustion engine. A deactivation strategy is determined and implemented. An evaluation is made of whether the engine is operating with an air/fuel imbalance between cylinders. When an imbalance is identified, an alternate deactivation strategy is implemented. Based on outcomes of the alternate deactivation strategy, a source cylinder of the air/fuel imbalance is identified, and fuel flow to the source cylinder is corrected.

A control device is included in a fuel injection system. The fuel injection system includes a low pressure pump, a high pressure pump, an accumulator, a fuel injection valve, a relief valve, and a return pipe. The high pressure pump increases a pressure of a fuel discharged from the low pressure pump and discharges high pressure fuel. The accumulator stores the high pressure fuel discharged from the high pressure pump. The relief valve is provided in a high pressure portion provided downstream from the high pressure pump and opens when a high pressure abnormality occurs in the high pressure portion. The return pipe returns the high pressure fuel in the high pressure portion to a low pressure portion provided downstream from the low pressure pump by the relief valve opening.

A method of generating an ROI profile for a fuel injector using machine learning and a constrained/limited training data set is disclosed. The method includes receiving a first plurality of measurement sets for a fuel injector when operating at a first target set point. Preferably, at least two measurement sets of the first plurality of measurement sets are selected to generate a first averaged ROI profile for the first target condition. The at least two selected measurement sets are then used to train a machine learning model that can output a predicted ROI profile for a fuel injector based on a desired pressure value and/or desired mass flow rate value. Training of the machine learning model preferably includes a predetermined number of iterations that induces overfitting within the model/neural network.

A vehicle includes a pump configured to discharge a fuel by reciprocating a plunger, a rail configured to store the fuel discharged from the pump, and a fuel injection valve configured to inject the fuel supplied from the rail. A controller for the vehicle includes a waveform obtaining unit and a phase shift obtaining unit. The waveform obtaining unit is configured to obtain a waveform of a fuel pressure in the rail as a function of time in a predetermined period. The phase shift obtaining unit is configured to obtain a phase shift based on the waveform obtained by the waveform obtaining unit. The phase shift is an offset between a timing the plunger reciprocated in the pump arrives at a first position and a timing a piston reciprocating in an internal combustion engine arrives at a second position.

A method for controlling an internal combustion engine, in which, based on a rail pressure signal, a first characteristic variable is specified that indicates a misfire, a misfire being recognized when the rail pressure signal does not have the expected curve.

Methods and systems are provided for estimating ethanol content in fuel, water content in fuel, and an age of the fuel in a vehicle engine. In one example, a method may include estimating fuel ethanol content, water content, or fuel age based on fuel rail temperature, and two or more of a resonant frequency (f) of pressure pulsations, a change in fuel rail pressure (δp), and a damping coefficient (α) of pressure pulsations in the fuel rail as estimated after a fuel injection or a pump stroke. One or more engine operating parameters may be adjusted based on the estimated fuel ethanol content, water content, and fuel age.

A storage device is configured to store a first mapping that receives, as an input, a first input variable including a cam phase variable on present and past phases of a cam, and output a pulsating variable on a pulsating component. The execution device is configured to acquire the first input variable and estimate the pulsating variable by applying the acquired first input variable to the first mapping. Therefore, it is possible to estimate the pulsating variable without providing a low-pressure fuel pressure sensor by estimating a fuel pressure variable by applying the first input variable to the first mapping.

A method and a system for determining a temperature for pressurized fuel included in a high pressure fuel system arranged for providing fuel to an engine are presented. The method includes determining a first temperature for a first fuel volume included in a first section of the high pressure fuel system, where the first section includes a common rail fuel system. The method further includes determining a second temperature for a second fuel volume included in a second section of the high pressure fuel system, where the second section includes at least one fuel injector arranged in a cylinder head of the engine. The method also includes the step of determining the temperature for the pressurized fuel based at least on the first temperature and on the second temperature.

An objective of the disclosure is to provide a method for calculating a one-dimensional (1D) spatial fluctuation in an unbranched high-pressure fuel pipe of a common rail system. The method includes the following steps: dividing a flow in the unbranched high-pressure fuel pipe according to a spatial length into sections for solving, to obtain forward and reverse pressure fluctuation forms; iteratively calculating forward and reverse pressure fluctuations propagating in a fuel pipe model to obtain fluctuations of various sections of the fuel pipe from an inlet to an outlet within one step, and calculating a flow velocity at a corresponding position in the pipe; and extracting a corresponding flow rate of the system, and substituting into an iterative calculation of the overall system to obtain an output pressure.