Abstract: Various methods and systems are provided for a fuel injector. In one example, a fuel injector includes a nozzle tip including a plurality of injection holes, a first needle biased against the nozzle tip via a first biasing member positioned within a first control volume, and a second needle surrounding a portion of the first needle and biased against the first needle and the nozzle tip via a second biasing member positioned within a second control volume. A needle actuator may be energized for different durations of time in order to move one or more of the first needle and the second needle relative to the nozzle tip.

Abstract: Various methods and systems are provided for health assessments of a fuel system. In one example, a fuel system includes a low-pressure pump operable to pump fuel from a fuel source at a first pressure, a high-pressure pump operable to increase the first pressure to a second pressure, a valve positioned between the low-pressure pump and the high-pressure pump and operable to control fuel flow to the high-pressure pump, a common fuel rail fluidly coupling the high-pressure pump to a plurality of fuel injectors coupled to cylinders of an engine, and a controller. The controller is operable to adjust an amount of valve electrical current supplied to the valve to reach a commanded pressure of the common fuel rail during cylinder firing conditions, the supplied valve electrical current adjusted based on a valve pre-firing correction factor for the valve obtained based on valve electrical current prior to cylinder firing commencing.

Abstract: Various systems are provided for delivering fuel to an engine. In one example, a system includes a controller and a fluid system configured to maintain a fluid at a pressure downstream of a check valve. The controller may be configured to determine if a leak is present in the fluid system based on a first pressure decay rate of the fluid system, and responsive to identifying that a leak is present in the fluid system, differentiate between an internal leak and an external leak based on a leak flow rate as fluid system pressure decreases.

Abstract: Various systems are provided for delivering fuel to an engine. In one example, a system includes a controller and a fluid system configured to maintain a fluid at a pressure downstream of a check valve. The controller may be configured to determine if a leak is present in the fluid system based on a first pressure decay rate of the fluid system, and responsive to identifying that a leak is present in the fluid system, differentiate between an internal leak and an external leak based on a leak flow rate as fluid system pressure decreases.

Abstract: Various methods and systems are provided for a fuel injector. In one example, a fuel injector includes a nozzle tip including a plurality of injection holes, a first needle biased against the nozzle tip via a first biasing member positioned within a first control volume, and a second needle surrounding a portion of the first needle and biased against the first needle and the nozzle tip via a second biasing member positioned within a second control volume. A needle actuator may be energized for different durations of time in order to move one or more of the first needle and the second needle relative to the nozzle tip.

Abstract: Various methods and systems are provided for diagnosing a rotating device. In one example, a system includes a rotating device and a RFID circuit coupled to the rotating device. The RFID circuit includes a RFID chip, an antenna, and a mechanical link designed to change impedance with a changing input from the rotating device.

Abstract: Various methods and systems are provided for health assessments of a fuel system. In one example, a fuel system includes a low-pressure pump operable to pump fuel from a fuel source at a first pressure, a high-pressure pump operable to increase the first pressure to a second pressure, a valve positioned between the low-pressure pump and the high-pressure pump and operable to control fuel flow to the high-pressure pump, a common fuel rail fluidly coupling the high-pressure pump to a plurality of fuel injectors coupled to cylinders of an engine, and a controller. The controller is operable to adjust an amount of valve electrical current supplied to the valve to reach a commanded pressure of the common fuel rail during cylinder firing conditions, the supplied valve electrical current adjusted based on a valve pre-firing correction factor for the valve obtained based on valve electrical current prior to cylinder firing commencing.

Abstract: Various methods and systems are provided diagnosing a valve. In one example, a system comprises a valve configured to regulate a fuel flow, and a controller configured to determine degradation of the valve based on an initial opening characteristic of the valve.

Abstract: Various methods and systems are provided for a multi-fuel capable engine. In one example, a system comprises an engine having at least one cylinder controlled via an intake valve, a first fuel system to deliver liquid fuel and a second fuel system to deliver gaseous fuel to the at least one cylinder, a variable valve timing actuation system to adjust one or more of an opening or a closing timing of the intake valve, and a controller. The controller is configured to, during a liquid fuel only mode, adjust the variable valve timing actuation system to close the intake valve at a first timing based at least on engine load, and during a multi-fuel mode, adjust the variable valve timing actuation system to close the intake valve at a second timing.

Abstract: Systems and methods for monitoring a vehicle determine a baseline wheel rotational speed and wheel rotational speeds of a wheel for different positions along an outer perimeter of the wheel. One or more deviations between the wheel rotational speeds and the baseline wheel rotational speed are determined, and the deviations between the wheel rotational speeds and the baseline wheel rotational speed are correlated with one or more identified positions of the positions along the outer perimeter of the wheel. One or more of damage to the wheel or damage to a drivetrain of the vehicle is identified based at least in part on the one or more deviations being correlated with the one or more identified positions.

Abstract: Various systems are provided for delivering fuel to an engine. In one example, a system includes a controller and a fluid system configured to maintain a fluid at a pressure downstream of a check valve. The controller may be configured to determine if a leak is present in the fluid system based on a first pressure decay rate of the fluid system, and responsive to identifying that a leak is present in the fluid system, differentiate between an internal leak and an external leak based on a leak flow rate as fluid system pressure decreases.

Abstract: Various methods and systems are provided for a multi-fuel capable engine. In one example, a system comprises an engine having at least one cylinder controlled via an intake valve, a first fuel system to deliver liquid fuel and a second fuel system to deliver gaseous fuel to the at least one cylinder, a variable valve timing actuation system to adjust one or more of an opening or a closing timing of the intake valve, and a controller. The controller is configured to, during a liquid fuel only mode, adjust the variable valve timing actuation system to close the intake valve at a first timing based at least on engine load, and during a multi-fuel mode, adjust the variable valve timing actuation system to close the intake valve at a second timing.

Abstract: Various methods and systems are provided diagnosing a valve. In one example, a system comprises a valve configured to regulate a fuel flow, and a controller configured to determine degradation of the valve based on an initial opening characteristic of the valve.

Abstract: Various methods and systems are provided for indexing an injector map and subsequently controlling fuel injection to an engine. In one embodiment, a non-transitory computer readable storage medium with memory comprises fuel injector activation data indexed in the memory according to an input parameter, instructions for determining a modified pressure value based on a determined pressure and a modified pressure function, and instructions for generating a fuel injector activation output by interpolating among the indexed fuel injector activation data with the modified pressure value as the input parameter.

Abstract: Various methods and systems are provided for diagnosing a rotating device. In one example, a system includes a rotating device and a RFID circuit coupled to the rotating device. The RFID circuit includes a RFID chip, an antenna, and a mechanical link designed to change impedance with a changing input from the rotating device.

Abstract: Systems and methods for monitoring a vehicle determine a baseline wheel rotational speed and wheel rotational speeds of a wheel for different positions along an outer perimeter of the wheel. One or more deviations between the wheel rotational speeds and the baseline wheel rotational speed are determined, and the deviations between the wheel rotational speeds and the baseline wheel rotational speed are correlated with one or more identified positions of the positions along the outer perimeter of the wheel. One or more of damage to the wheel or damage to a drivetrain of the vehicle is identified based at least in part on the one or more deviations being correlated with the one or more identified positions.

Abstract: Various methods and systems are provided for indexing an injector map and subsequently controlling fuel injection to an engine. In one embodiment, a non-transitory computer readable storage medium with memory comprises fuel injector activation data indexed in the memory according to an input parameter, instructions for determining a modified pressure value based on a determined pressure and a modified pressure function, and instructions for generating a fuel injector activation output by interpolating among the indexed fuel injector activation data with the modified pressure value as the input parameter.