A control device can execute a first diagnosis process of, when first execution conditions are met, diagnosing whether an air-fuel ratio sensor has an abnormality while executing a motoring process, and a second diagnosis process of, when second execution conditions are met, diagnosing whether a GPF has an abnormality while executing the motoring process. In an execution determination process, the control device prohibits execution of both the first diagnosis process and the second diagnosis process when at least either the first execution conditions or the second execution conditions are not met, and permits execution of both the first diagnosis process and the second diagnosis process when both the first execution conditions and the second execution conditions are met.

A control device for a series hybrid vehicle, the series hybrid vehicle including: an engine, a catalyst that is disposed in an exhaust path of the engine, a generator that generates electric power using power output from the engine, a battery that stores the electric power generated by the generator, and a traction electric motor that is driven with electric power of the battery, the control device including an electronic control unit configured to: acquire information on a temperature of the catalyst; and, when the information on the temperature of the catalyst is information corresponding to the temperature of the catalyst being equal to or higher than a predetermined temperature, change an operating point of the engine to an operating point that reduces a temperature of the exhaust gas while generating the electric power by the generator.

A controller for a hybrid electric vehicle executes an intake gas flow rate adjusting process, a motor-driven actuation process, a fuel vapor adjusting process, and a starting process. The intake gas flow rate adjusting process includes adjusting an opening degree of a throttle valve to an open state. The motor-driven actuation process includes controlling a motor-generator to perform motor-driven actuation of the internal combustion engine. The fuel vapor adjusting process includes adjusting an opening degree of a fuel vapor adjusting valve during the motor-driven actuation process, thereby allowing fuel vapor to flow through a fuel vapor passage. The starting process includes starting the internal combustion engine by controlling an ignition device to perform ignition during the motor-driven actuation process.

Methods and systems are provided for on-board diagnostics of an exhaust gas recirculation (EGR) system of an engine coupled to a hybrid vehicle. In one example, a method may include, upon receiving an engine shut-down request, prior to engine spin-down, rotating the engine at an idling speed via an electric motor and carrying out diagnostics of the EGR system. EGR diagnostics may include estimating a ratio of accumulated difference between a measured EGR flow and an EGR limit to accumulated intake air flow, over a duration of time, and indicating EGR system degradation in response to the ratio being higher than a threshold.

A vehicle system includes an internal combustion engine including a fuel injection valve configured to inject fuel into an intake port and a throttle valve configured to control intake air amount for controlling engine torque, and being mounted on a vehicle. The vehicle system further includes a control device configured to control the vehicle. The control device includes a fuel increment controlling component that executes a fuel increment control to make the air-fuel ratio richer than the stoichiometric air-fuel ratio in a plurality of cycles started from a fuel injection start cycle at the time of engine start-up. Where a torque rate correlation value correlated with a torque rate that is a time rate of increase of the engine torque is lower, the fuel increment controlling component deceases a total fuel injection amount in the plurality of cycles.

When a temperature of a catalyst in an exhaust emission control device mounted in an exhaust system of an engine is equal to or higher than a predetermined temperature at a time of a request for stopping the engine, a hybrid vehicle including the engine and a motor continues fuel injection of the engine until satisfaction of a predetermined condition and stops fuel injection of the engine on satisfaction of the predetermined condition. When the temperature of the catalyst is lower than the predetermined temperature at the time of the request for stopping the engine, on the other hand, the hybrid vehicle immediately stops fuel injection of the engine.

An engine power suppressing device includes a controller which controls an operation of a power changing element which changes engine power for driving a vehicle; and an environment sensor which detects an environment parameter indicating an environment in which the vehicle is used, wherein the controller determines whether or not a power suppressing condition in which a vehicle state is a state in which the engine power is to be suppressed, is met, wherein in a case where the controller determines that the power suppressing condition is met, the controller sets a suppressing value for the power changing element to suppress the engine power, and compensates the suppressing value based on the environment parameter detected by the environment sensor.

Introduction of a low fuel consumption technique such as downsizing turbos and idling stop decreases an intake pipe negative pressure (pump loss) of an internal combustion engine, and results in difficulty in emitting (evaporative fuel purge) a volatile fuel (volatile fuel) in a fuel tank by the negative pressure of the intake pipe of the internal combustion engine. A control device includes: a purge control unit which controls a purge valve which emits a volatile fuel of a fuel tank or a canister to an intake pipe of an internal combustion engine; and a power transmission control unit which controls a power transmission mechanism between the internal combustion engine and a drive wheel, and, in a state where the power transmission control unit disconnects a clutch, and the vehicle is coasting, the purge control unit opens the evaporative fuel valve and purges an evaporative fuel to the intake pipe.

A method and a system for improving operation of a hybrid vehicle are presented. In one example, an engine exhaust after treatment device is cooled at an opportunistic time. The approach may provide improved cooling for exhaust after treatment devices and it may also improve vehicle emissions.

A control device of a hybrid vehicle, the hybrid vehicle including an engine, a motor as a traveling power source, and a battery in which electric power to be supplied to the motor is charged, includes: a transient operation controller performing, when absolute values of an outputtable electric power and a chargeable electric power of the battery are small at a time of a transient operation of the engine, a transient operation of controlling an operating point of the engine within a wide range from low output to high output, at a position where a thermal efficiency is lower than the thermal efficiency at a time of a steady operation, and of controlling the engine to be in a combustion state where a margin to a combustion limit is greater than the margin in the steady operation.