A system may include at least one engine bank including a plurality of fuel injectors. At least one exhaust temperature sensor is coupled to the engine bank(s). The exhaust temperature sensor(s) is configured to output at least one temperature signal regarding an exhaust temperature of the engine bank(s). A traction system is configured to output at least one electrical signal related to a power output of a vehicle. A control unit is coupled to the exhaust temperature sensor(s) and the traction system. The control unit is configured to receive the temperature signal(s) and the electrical signal(s). The control unit is configured to determine a mechanical and electrical health of the plurality of the fuel injectors by determining a temperature differential value of the temperature signal(s) and a power differential value related to the electrical signal(s), and analyzing a combination of the temperature differential value and the power differential value.

Methods and systems are described for diagnosing degradation of a vacuum actuator in an engine system. An example method comprises indicating degradation of the vacuum actuator based on an estimate of flow of air into and out of a vacuum reservoir. The estimate is further based on flow of air generated via each of an aspirator in the intake system, an actuation of the vacuum actuator, and leakage during the actuation of the vacuum actuator.

A control device for an internal combustion engine controls a control object device based on an output value of a relative angle sensor that detects a relative angle of an output shaft of an actuator, and an output value of an absolute angle sensor that detects an absolute angle of a drive shaft coupled to the output shaft of the actuator via a speed reducer. In this event, the control device for the internal combustion engine corrects an output value of the absolute angle sensor based on an absolute angle of the drive shaft that is obtained from an output value of the relative angle sensor using, as a reference point, an output value of the absolute angle sensor at the start-up of the internal combustion engine, and an output value of the absolute angle sensor.

Systems and methods are provided herein for tracking degradation of a high-pressure fuel pump. In one example, a fuel system controller is configured to receive an output pressure signal from a pressure sensor, transform the output pressure signal to the frequency domain to generate frequency content of the output pressure signal, and diagnose a condition of a fuel pump based at least in part on the frequency content of the output pressure signal, the fuel pump fluidly coupled to a fuel injector via a common fuel rail, and the fuel injector is operable to inject fuel to a cylinder of an engine.

A control device for an engine, the engine includes an exhaust gas control apparatus that is configured to store NOx and react NOx with a reduction agent. The control device includes an electronic control unit. The electronic control unit is configured to: (i) execute a rich spike control, the rich spike control is a control executed to temporarily change an in-cylinder air-fuel ratio from a leaner air-fuel ratio than the stoichiometric air-fuel ratio to the stoichiometric air-fuel ratio or a richer air-fuel ratio than the stoichiometric air-fuel ratio, and (ii) vary an overlap amount of an intake valve and an exhaust valve such that the overlap amount is less during non-execution of the rich spike control than during execution of the rich spike control, in an operation range where a pressure of the intake port becomes higher than a pressure of the exhaust port.

A driving mode setting part sets a driving mode when a vehicle travels by automatic driving. An item setting part sets a prioritized diagnosis. A storage part stores plural diagnosis conditions provided in correspondence to each diagnosis item. A target setting part sets a control target value. A motive power source part controls a motive power source based on the control target value. Each diagnosis item is assigned to the driving mode, for which the diagnosis condition is most easily satisfied. The item setting part sets, as a prioritized item, the diagnosis item assigned to the set driving mode. When the prioritized item is set, the target setting part sets the control target value so that the motive power source attains a state, which is close to the diagnosis condition of the prioritized item.

A control device of an internal combustion engine calculates on the basis of the air-fuel ratio difference a correction for the estimated fuel supply amount correction for correcting the estimated fuel supply amount to make the estimated and detected air-fuel ratios correspond to each other and calculates correction values for the fuel supply difference compensation and the air amount detection difference compensation by dividing the correction value for the estimated fuel supply amount correction, using the fuel supply and air amount detection difference proportions, and performing the air-fuel ratio control, using the corrected estimated fuel supply and detected air amounts. The correction value for the estimated fuel supply amount correction is divided to the correction values for the fuel supply difference compensation and the air amount detection difference compensation such that a value equivalent to the air-fuel ratio difference becomes equal to the air-fuel ratio difference, using these correction values.

Provided is a load drive device capable of diagnosing a failure of an output terminal of the load drive device before a charging voltage stabilizes in a configuration in which a capacitor is connected to an output terminal of the load drive device that drives an inductive load. In the load drive device according to the present invention, a capacitor is connected between a load terminal and a ground terminal, and the presence or absence of a failure of the load terminal is diagnosed on the basis of a current flowing between an internal power supply included in a diagnosis circuit and the load terminal.

Methods for controlling a Methods for controlling a valve disposed at an engine of a vehicle are disclosed. In one form of the disclosure, the method includes: determining whether an engine is an idle state; measuring a fuel pressure of the engine when the engine is the idle state; comparing the measured fuel pressure with a first threshold value; and operating the valve by applying a current to a valve operation coil when the measured fuel pressure is equal to or less than the first threshold value for a predetermined time or longer.

Systems and methods for improving compressor recirculation valve operation of an engine that includes a compressor are presented. The systems and methods adjust a position of a waste gate while the compressor recirculation valve is operated in a closed loop mode to maintain engine intake manifold throttle inlet pressure during a diagnostic mode to adapt operation of the compressor recirculation valve.