A control device for an internal combustion engine including a variable compression ratio mechanism for changing a compression ratio by using an electric actuator prohibits control of changing the compression ratio to a higher compression ratio when a failure occurs in the variable compression ratio mechanism. Thereby, upon failure occurrence, the compression ratio of the variable compression ratio mechanism at the time of the failure occurrence is maintained or reduced to less than this compression ratio so as to protect the electric actuator and prevent abrupt changes in torque.

An abnormality flag is set when a first abnormality determination condition is established in an abnormality diagnosis of a fuel pressure sensor and it is determined that an abnormality occurs. In a case where the abnormality flag is kept cleared, when a fuel pressure detection value of the fuel pressure sensor is kept fixed for a prescribed time T2 or more and a second abnormality determination condition is established, a partial lift injection is prohibited, such that an injection control of a fuel injection valve is performed so as to perform a fuel injection without performing the partial lift injection.

A method of determining a learning area of injector opening duration according to the present exemplary embodiment divides an entire control area for controlling opening duration of an injector into a learning map area which needs learning and a reference map area which uses an already prepared reference map as is without learning, and a period from a minimum injection time to a minimum linear injection time of the injector is determined as the learning map area, and a period from the minimum linear injection time to a maximum injection time is determined as the reference map area.

A control device for a vehicle includes a failure detector to detect failure in a cooling device to cool an internal combustion engine of the vehicle. An acceleration operation sensor is to detect an acceleration operation amount indicating a target acceleration. Circuitry is configured to control a power output from the internal combustion engine in accordance with the acceleration operation amount, control an air fuel ratio of air-fuel mixture in the internal combustion engine to be in a richer side with respect to a predetermined air fuel ratio if the acceleration operation amount exceeds a high load threshold, limit the power output from the internal combustion engine if the failure detector detects the failure, and prohibit the air fuel ratio from being controlled to be in the richer side even if the acceleration operation amount exceeds the high load threshold if the failure detector detects the failure.

An engine includes a low-pressure delivery pipe that stores fuel to be injected from port injection valves, a feed pump that supplies the fuel to the low-pressure delivery pipe, a high-pressure delivery pipe that stores the fuel to be injected from in-cylinder injection valves, a high-pressure pump driven in response to rotation of the engine, and a fuel pressure sensor that detects a pressure of the fuel stored in the low-pressure delivery pipe. An engine ECU controls the feed pump based on a detection value from a fuel pressure sensor, and when the engine ECU executes an abnormality diagnosis of the fuel pressure sensor, the engine ECU increases a rotational speed of the engine to be higher than a rotational speed when the engine ECU does not execute an abnormality diagnosis of the fuel pressure sensor. This improves the accuracy of an abnormality determination of the fuel pressure sensor.

A method for regulating a fuel delivery system without a pressure sensor. The fuel delivery system has a fuel delivery pump, an electric motor, and an evaluation unit. The fuel delivery pump is driven by the electric motor, which is actuated using control variables such that a prespecifiable fuel delivery is achieved. At least two different submethods are executed for ascertaining control variables, which are ascertained in the respective submethod and are supplied to an evaluation unit. The control variables are evaluated regarding their plausibility in the evaluation unit and the electric motor is actuated based on the ascertained control variables from only one or a plurality of submethods.

An internal combustion engine includes a throttle valve, an EGR passage, an EGR valve, a valve mechanism that adjusts opening and closing characteristics of an intake valve or an exhaust valve of the internal combustion engine, and a controller that controls the throttle valve, the EGR valve and the valve mechanism, based on request torque that is requested of the internal combustion engine. The controller is configured to execute evacuation traveling control that operates the throttle valve to fully open, calculates a target intake air flow amount for achieving the request torque based on an effective opening area of the EGR valve which is stuck, and operates the valve mechanism in accordance with the target intake air flow amount, in at least one time period while the request torque is reducing when the EGR valve is stuck in an open state.

A valve (4, 4) for a fuel system for a combustion engine: A ball retainer (26) is provided with a cavity (28) to accommodate a ball (22). The ball (22) has a first seal surface (30) to cooperate with and abut sealingly against a seat (32). The ball retainer (26) has a secondary seal surface (34) to cooperate with and abut sealingly against the seat (32) when the ball (22) is not in the ball retainer (26). Also, a method for controlling a fuel system for a combustion engine.

A method for enforced discharge of a hybrid vehicle is aimed at discharging a voltage formed in a high-voltage system of a hybrid vehicle to safely remove risk factors due to high voltage when enforced discharge is requested. The method includes determining whether enforced discharge is requested, speed-controlling a motor connected to an engine so as to transmit power to the engine to reduce speed of the motor to zero revolutions per minute, stopping the engine connected to the speed-controlled motor when the enforced discharge is requested, and performing enforced discharge control for enforced-discharging a voltage of a high-voltage system when the engine is stopped.

Methods and systems for simultaneously operating port fuel injectors and direct fuel injectors of an internal combustion engine are described. In one example, operation of a port fuel injector is deactivated in response to an indication of reduced performance of a direct fuel injector so that degradation of the direct fuel injector may be reduced.