The invention relates to a method (200) for operating an internal combustion engine (110) having at least one catalytic converter (122), wherein control interventions of a lambda control for controlling an exhaust gas composition of the internal combustion engine are deactivated, comprising ascertaining a current exhaust gas composition upstream of the at least one catalytic converter (122), determining a current oxygen fill level of the at least one catalytic converter (122) on the basis of the ascertained current exhaust gas composition, ascertaining (210) a planned control intervention on a composition of an air-fuel mixture supplied to the internal combustion engine (110) on the basis of the determined current oxygen fill level of the at least one catalytic converter, ascertaining a current exhaust gas composition (123) downstream of the at least one catalytic converter (122), ascertaining a future exhaust gas composition (123) downstream of the at least one catalytic converter (122) resulting on the basis of an air-fuel mixture already supplied to the internal combustion engine (110), and reactivating the lambda control and specifying (260) a control intervention to be carried out as a function of the planned control intervention and the current exhaust gas composition (123) downstream of the at least one catalytic converter (122), and/or as a function of the planned control intervention and the future exhaust gas composition. Furthermore, a processing unit (130) and a computer program for carrying out such a method (200) are proposed.

Methods and systems are provided for a diagnostic routine of a variable displacement engine (VDE) of a vehicle to detect non-deactivated valves of deactivated cylinders due to a degraded valve deactivation mechanism. In one example, a method comprises, during operation of the VDE with one or more cylinders of the VDE deactivated, calculating a variation in a fast-sampled signal outputted by one or more exhaust gas oxygen (EGO) sensors of the VDE over a plurality of engine cycles; determining that the variation is greater than the threshold variation; and in response, indicating that valves of the one or more cylinders are not deactivated. A second method comprises estimating a throttle air flow rate and an engine air flow rate of the VDE; and indicating non-deactivated valves of one or more deactivated cylinders if the throttle air flow rate exceeds the engine air flow rate by a threshold.

A control method of an engine system is a method of controlling the engine system including an engine with a combustion chamber; a fuel injection valve configured to supply fuel to the engine; and an air-fuel ratio sensor provided in a flow path of exhaust gas from the engine. In the control method, feedback control is performed so that an air-fuel ratio in the combustion chamber becomes a target value by controlling the fuel injection valve, using an air-fuel ratio measured value obtained by the air-fuel ratio sensor. In the feedback control, a transfer function is used, the transfer function being obtained by system identification of a plant having the air-fuel ratio in the combustion chamber serve as an input and the air-fuel ratio measured value obtained by the air-fuel ratio sensor serve as an output. In the control method, a filtering process is performed to an air-fuel ratio measured value used in the feedback control, the filtering process cutting a component having a response speed faster than a delay indicated by the transfer function.

Methods and systems are provided for a vehicle engine having a pre-chamber ignition system. In one example, a method may include adjusting one or more of an air injection amount and a fuel injection amount to a pre-chamber of an engine based on an air injection offset and a fuel injection offset learned while discontinuing fueling to cylinders of the engine and reducing air flow through the engine. In this way, air and fuel may be more accurately provided to the pre-chamber, thereby decreasing an occurrence of pre-chamber misfire.

A gas sensor element comprising a long plate-like element body and a porous protective layer protecting a surface of the element body, wherein the element body has a gas detection part at an end thereof on one end face side in a longitudinal direction, and the protective layer includes an end face part covering the one end face in laminate, side face parts covering side faces connected to the one end face in laminate, and corner parts where two adjacent ones of the end face part and the side face parts meet. An outer surface of one or more of the end face part and the side face parts has a concave shape that is smoothly continuous with the corner parts and configured such that a layer thickness increases toward the corner parts.

A method of operating an engine is provided. An exhaust valve actuation fault is detected for a first exhaust valve associated with a first cylinder during a first working cycle. In response to the detection of the exhaust valve actuation fault, fueling to at least the first cylinder is cut off. Actuation of the first exhaust valve is attempted in second working cycles that follow the first working cycle, wherein the second working cycles are not fueled. Whether or not the first exhaust valve actuated properly during the second working cycles is determined. Operation of the first cylinder is resumed when it is determined that the first exhaust valve actuated properly. Operation of the first cylinder is not resumed when it is determined that the first exhaust valve did not actuate properly.

A turbocharger system (1) of a combustion engine (4) comprises a turbocharger turbine (5) operable by exhaust gases, a valve (7) configured to control gas flow of pressurized gas from a pressurized gas reservoir (6) to the turbocharger turbine (5), and a sensor (8). Turbocharger system operation comprises injecting a test pulse of pressurized gas from the pressurized gas reservoir (6) to drive the turbocharger turbine (5) by means of controlling the valve (7), detecting an impact of injected pressurized gas on the turbocharger turbine (5) by means of the sensor (8), collecting data from the sensor (8), and diagnosing the turbocharger system (1) by evaluating an operational response of the turbocharger turbine (5) as a result of the injected test pulse of pressurized gas, based on the collected data.

The invention relates to a method for operating a fuel supply pump of a vehicle, the vehicle comprising a combustion engine system and a gearbox, the method comprising the steps of: determining one or more operational values of at least one operational parameter of the combustion engine system; determining a reduction of a fuel provision rate to the combustion engine system; determining whether a gear step change of the gearbox is at hand, on the basis of the determined one or more operational values of the at least one operational parameter; and in case a gear step change of the gearbox is at hand, controlling operation of the fuel supply pump so as to maintain fuel supply pump speed.

A method detects a fault, in particular coking, in the intake tract of an internal combustion engine with direct fuel injection, a throttle valve, and a variable intake valve lift controller. The method has the steps of a) carrying out a first quantity deviation test, by which a first air ratio value is ascertained that is formed from a lambda value, which is measured during the first quantity deviation test, and a desired lambda value of the fuel combustion in the fuel chambers of the internal combustion engine, wherein in the first quantity deviation test, a load control is carried out by the variable intake valve lift controller; b) carrying out a second quantity deviation test, by which a second air ratio value is ascertained that is formed from a lambda value, which is measured during the second quantity deviation test, and a desired lambda value of the fuel combustion in the fuel chambers of the internal combustion engine, wherein in the second quantity deviation test, a load control is carried out by the throttle valve; and lastly c) determining a comparison result from the first air ratio value and the second air ratio value, the presence of a fault in the intake tract of the internal combustion engine being detectable using the comparison result.

Systems and methods for controlling a gasoline urea selective catalytic reductant catalyst are described. In one example, an observer is provided that corrects an estimate of an amount of NH.sub.3 that is stored in a SCR. The amount of NH.sub.3 that is stored in the SCR is a basis for generating additional NH.sub.3 or ceasing generation of NH.sub.3.