A method of detecting a defeat device includes: determining turbo operation when a turbocharger of a vehicle is operated; determining flow rate of the air to be applied to an intake manifold wherein it is determined whether which flow rate out of a first flow rate of the air passing through a throttle valve and a second flow rate of the air measured by a hot-film air mass flow (HFM) sensor is used as the flow rate of the intake manifold; determining whether pressure in the intake manifold is in a normal range based on the flow rate of the intake manifold; and determining that the defeat device is installed if it is determined that the pressure in the intake manifold is not in the normal range and storing information of the defeat device.

The invention relates to a method and a device, in particular a control and evaluation unit, for operating at least one exhaust gas sensor for monitoring the functionality of an emission control system in the exhaust tract of an internal combustion engine, wherein the exhaust gas sensor is operated at least intermittently at high temperatures and has a thermal shock sensitivity inherent to the design, and in which a heating phase can be implemented at least intermittently prior to a regeneration phase or prior to a measuring operation phase, wherein a clearly lower temperature is set in this heating phase in comparison to the regeneration temperature or the measuring operation temperature. According to the invention, the function for dew point recognition and re-release of a dew point end is adaptively implemented and influenced by at least one water detection criterion or at least one flood detection criterion. By this means, an improved dew point detection is achieved after driving through water, as a result of a significant reduction of tolerances and an earlier release of the dew point end for the exhaust gas sensor.

After a system-off state has continued for a preset, time period since a system-off operation, on satisfaction of abnormality diagnosis prerequisites including a condition that a warm-up determination parameter indicating a degree of warm-up of an engine at a system-off time is equal to or greater than a predetermined value, characteristic abnormality diagnosis is performed to determine whether a characteristic abnormality occurs in a fuel pressure sensor. For a time period from a system-on operation to a system-off operation, the warm-up determination parameter is incremented when the engine is in operation, while being decremented after satisfaction of a predetermined condition when the engine is not in operation.

An engine of the invention includes an engine main unit having cylinders, an intake line, an exhaust line, a supercharger, a turbo sensor detecting a rotational speed of the supercharger, a control device controlling, based on signal from the turbo sensor, an operating state of the engine main unit that has a correlation with the rotational speed of the supercharger, and a crank angle sensor detecting a rotation angle of a crankshaft. The control device recognizes timings at which the cylinders are in a top dead center state based on detection signals of the crank angle sensor and, also, makes a disconnection judgment for the turbo sensor at non-top dead center timings that are within one combustion cycle of the engine main unit and at which none of the plurality of cylinders are in a top dead center state.

A method for diagnosing the function of an exhaust gas sensor in an exhaust gas. The function is evaluated here according to whether during a heating phase an operating temperature of the exhaust gas sensor has been reached for a predefined time period. It is taken into account here whether during the heating phase sufficient heating power has been available to carry out a successful heating phase.

A method for identifying faulty components of a fuel injection system is disclosed, wherein a secondary injection is performed individually by each injector during a test routine, after the secondary injection several predefined parameters of the fuel injection system are determined, and a combined assessment of the determined parameters is used to draw conclusions about whether or not components of the fuel injection system are faulty.

Methods and systems are described for an engine with a cam torque actuated variable cam timing phaser. Phaser positioning control is improved by reducing inaccuracies resulting from inadvertent spool valve and/or phaser movement when the spool valve is commanded between regions. In addition, improved spool valve mapping is used to render phaser commands more consistent and robust.

Methods and systems are provided for diagnosing an in-range error of a pressure sensor arranged downstream of a lift pump in a fuel system of a vehicle. In one example, a method may include performing feedback control of the lift pump based on output of the pressure sensor, monitoring the pressure sensor output for flattening during the application of the voltage pulses, and adjusting operation of the fuel system depending on whether the pressure sensor output flattens for at least a threshold duration, which is indicative of an in-range error. The method may further include dynamically learning a setpoint pressure of a pressure relief valve of the fuel system and a fuel vapor pressure within the fuel system by monitoring pressure sensor output while adjusting the duty cycle of voltage pulses applied to the lift pump.

On-board diagnostic monitoring of a two-stroke cycle, opposed-piston engine includes diagnostic monitoring of an air handling system equipped with a supercharger to determine whether the supercharger is functioning properly.

It is intended to, when abnormality in either one of two rotation detection sections with different detection frequencies occurs, quickly and highly accurately detect the abnormality to favorably deal with abnormality occurring during low engine rotation. It is determined that abnormality is present in the rotation phase detection section, when an absolute value of difference between an actual VTC angle detected by a rotation phase detection section and an integrated value of a VTC change angle detected by motor rotation sensor 201 with the higher detection frequency than the frequency of detection of the actual VTC angle by the rotation phase detection section is equal to or greater than a predetermined value.