A method of detecting failures of an engine control computer including at least: a hardware layer, a software layer comprising at least one activation cycle of the load m phase(s) of activation of said load with: actuation of the load, first timeout, deactivation of the load, second timeout. The method of detecting failures includes a measurement time window during which the following are carried out: an initialization of the measurement variables, detection of an actuation of the load, an action of reinitializing the engine control computer if at least one of the following conditions is valid: ΔT1>ΔT1_ref, ΔT2<ΔT2_ref, ΔT3>ΔT3_ref, ΔT4<ΔT4_ref.

Various embodiments may include a method for checking the plausibility of the functionality of a crankcase ventilation system of an internal combustion engine, wherein crankcase ventilation system has a crankcase, an intake tract equipped with an intake manifold, and a connecting line arranged between the crankcase and the intake manifold, the method comprising: detecting an occurrence of a negative load change; in response, comparing a measured intake manifold pressure with a modelled intake manifold pressure using acquired operating variables of the internal combustion engine and of a crankcase model; and determining on the basis of the comparison result whether the connecting line arranged between the crankcase and the intake manifold becomes blocked or drops out.

A method (50) for isolating a fault within an engine system (10) including an engine control module (40) and a diagnostics module (36) includes determining, by the engine control module (40), a plurality of parameters of the engine system (10), calculating a likelihood of the fault using a log-likelihood ratio analysis of data within the engine control module (40), and providing a plurality of fault determinations and the likelihood of each of the plurality of fault determinations using plurality of parameters and the diagnostics module (36) of the engine system (10).

With a simple configuration, responsiveness between an electronic control unit and a load drive circuit is monitored without deteriorating characteristics of the load drive circuit. The load drive circuit according to the present invention diagnoses an abnormality in responsiveness of a switch element that drives a load based on a drive command of the switch element and a signal at an output terminal of the switch element.

A hybrid vehicle includes an engine, an exhaust gas recirculation device, a traveling motor, and a control device. The exhaust gas recirculation device includes a communication pipe that allows an exhaust pipe and an intake pipe of the engine to communicate with each other and a valve that is provided in the communication pipe. The control device is configured to perform foreign matter removal control for opening and closing the valve when foreign matter caught in the valve is detected and the hybrid vehicle stops.

Methods and systems are provided for diagnosing a cylinder valve deactivation mechanism in an engine system having cam-actuated valves. Movement of a latch pin of the deactivation mechanism is inferred from an induction current generated by a solenoid coupled to the latch pin, and the inferred movement is used to diagnose operation of cylinder valve deactivation mechanism. The inferred movement and a profile of the induction current is also used to estimate camshaft and crankshaft timing for improved cylinder fuel delivery in the absence of a camshaft sensor.

An engine system is provided with an electronic throttle device to regulate intake amount to the engine, an EGR device (EGR valve) to recirculate a part of exhaust gas of the engine to the engine as EGR gas, and an electronic control unit (ECU) to control the electronic throttle device and the EGR valve based on an operating state of the engine. The ECU performs feedback control of the electronic throttle device such that a detected engine rotation number becomes a target idle rotation number, and sets the target idle rotation number to a predetermined first set value for avoiding engine stall until a predetermined time elapses from start of deceleration and then shifts the target idle rotation number to a second set value lower than the first set value after the predetermined time elapses.

A controller for controlling a fuel injection valve and a fuel pressure adjustment mechanism integrates a deposition amount of deposits per unit time, and estimates a deposition amount of deposits on an injection hole of the fuel injection valve. The controller causes the fuel pressure adjustment mechanism to increase a fuel pressure, when the estimated deposition amount exceeds a predetermined value, and corrects the unit deposition amount acquired by the deposition amount estimation according to the set fuel injection timing of the fuel injection valve. The controller corrects such that as compared with the unit deposition amount when the fuel injection timing is set to a first timing away from a top dead center of the piston by a first period, the unit deposition amount decreases when the fuel injection timing is set to a second timing away by a second period longer than the first period.

A current control circuit for an ignition system (i.e., igniter current limiter) is disclosed. The current control circuit can reduce a coil current over a soft shut down (SSD) period using an insulated gate bipolar transistor (IGBT) that is controlled by a negative feedback loop, which controls the current limit of the IGBT according to a SSD profile. In order to prevent an unwanted current rise during the soft shut down period, the current control circuit compares a gate voltage of the IGBT to a reference signal and based on the comparison can enable the SSD profile to include a fast ramp. The fast ramp quickly lowers the current limit of the IGBT so that the coil current equals the current limit and can be controlled by the negative feedback loop.

A control method can be used for securing continuously variable valve duration (CVVD) startability when a CVVD error is recognized by a CVVD controller during an operation of a CVVD system. The control method includes performing engine startability securing control for solving the CVVD error by applying a starting air volume to starting of an engine through at least one of a valve position fixing value, a valve position threshold, or an immediately previous valve position value.