A system includes a controller having a control signal generation unit that provides control signals to actuate one or more valve actuators of an engine to a desired position, and control signals to modify one or more operational parameters and an operational mode of the engine. A parameter signal process unit receives parameter signals corresponding to at least one operational parameter of the engine, and at least one sensor coupled to the engine. At least one sensor corresponds to a position of a valve. A failure detection unit generates at least one fault code corresponding to one or more failure modes. A failure mode isolation unit isolates a failure mode from the one or more failure modes in response to modifying the operational parameters or the operational mode, causing actuation of the valves to a desired position, or receiving the parameter signals and the sensor.

The abrupt cessation or run-away of a combustion engine may damage the combustion engine and pose a safety hazard to the surrounding environment. The combustion engine operational mode may be controlled, regulated or maintained by regulating the combustion mixture of the combustion engine. The oxidizer flow, a material or both of the combustion mixture may be regulate to create or form a combustion material that is outside a combustible range such that the combustion engine is placed or maintained in a spin-down operational mode. The material added to the combustion mixture may include a combustible, non-combustible, oxidizer, or exhaust material. A brake may also provide a secondary mechanism to maintain or place the combustion engine in a spin-down mode.

A method and a device for detecting an abnormality in a click heatmap are provided. In the method, a to-be-detected region in a first click heatmap is determined. Click source data of the to-be-detected region is compared with click source data of a normal click region, to obtain a first comparison result. Whether the to-be-detected region is an abnormal click region is determined based on the first comparison result.

The abnormality diagnosis system 1, 1, 1 of an ammonia detection device 46, 71 comprises: an air-fuel ratio detection device 41, 72 arranged in the exhaust passage 22 at the downstream side of the catalyst 20; an air-fuel ratio control part 51 configured to control an air-fuel ratio of exhaust gas; and an abnormality judgment part 52 configured to judge abnormality of the ammonia detection device. The air-fuel ratio control part performs rich control making the air-fuel ratio of the inflowing exhaust gas richer than a stoichiometric air-fuel ratio. The abnormality judgment part judges that the ammonia detection device is abnormal if, after start of the rich control, an output value of the ammonia detection device does not rise to a reference value before the air-fuel ratio detected by the air-fuel ratio detection device falls to a rich judged air-fuel ratio richer than a stoichiometric air-fuel ratio.

An engine controller is provided. A second calculation process calculates an intake air amount without using an output of an air flow meter. A second determination process determines whether an intake air pulsation in an intake passage is great without using the output of the air flow meter. When the intake air pulsation is determined to be great by at least one of a first determination process and the second determination process, a calculation method switching process selects the calculated value of the intake air amount obtained by the second calculation process as a calculated value of the intake air amount used to determine an operation amount of an actuator.

An engine control apparatus includes first and second fuel injection amount calculators, a fuel injection controller, an EGR valve controller, and an EGR valve diagnosis unit. The first and second fuel injection amount calculators are configured to calculate first and second fuel injection amounts on the basis of a detected intake air amount and detected pressure in an intake pipe, respectively. The fuel injection controller is configured to control a fuel injection apparatus for an engine on the basis of a correction fuel injection amount that is a result of addition of the first and second fuel injection amounts respectively multiplied by first and second weight coefficients. When the fuel injection is restarted after diagnosis of the EGR valve carried out by the EGR valve diagnosis unit, the fuel injection controller increases the second weight coefficient, and thereafter gradually increases and reduces the first and second weight coefficients, respectively.

Methods and systems are provided for diagnosing whether one or more intake air oxygen sensors positioned in an intake of an engine of a vehicle, are functioning as desired. In one example, a method comprises injecting fuel into one or more cylinders of the engine without combustion, routing un-combusted hydrocarbons from the one or more cylinders to the intake via a crankcase ventilation system, and indicating whether the one or more intake air oxygen sensors are functioning as desired based on a response of the one or more intake air oxygen sensors. In this way, the one or more intake air oxygen sensors may be periodically diagnosed which may improve engine operation, and reduce engine degradation, particularly with regard to hybrid electric vehicles with limited engine run-time.

A method for operating an internal combustion engine is provided, which has a combustion unit, including a combustion chamber; a fresh gas tract; an exhaust tract, including an exhaust gas sensor integrated therein; and a fuel tank system. During an operation of the internal combustion engine, while purge gas is conducted via a purge gas line a hydrocarbon content of the purge gas is ascertained with the aid of the HC sensor, and the mass flow of the purge gas is also ascertained, and a fuel mass flow introduced into the fresh gas tract is ascertained from these values in combination and a quantity of fuel introduced into the combustion chamber and/or into the fresh gas tract with the aid of at least one fuel injector is adapted.

A method and a device for knock control of an internal combustion engine, a knock signal of a cylinder of the internal combustion engine being measured by a knock sensor and, on the basis thereof, a knock intensity is generated. The knock intensity is compared to a reference level in order to classify a combustion as a knocking or non-knocking combustion. Moreover, an arrangement is provided, which takes the level of the knock intensity into account for the determination of the reference level.

Methods and systems are disclosed for operating an engine that includes a knock control system that may determine contributions of individual noise sources to an engine background noise level. The contributions of the individual noise sources may be the basis for establishing the presence or absence of knock in one or more engine cylinders.