A failure diagnosis device for an in-cylinder pressure sensor includes an in-cylinder pressure sensor, and a controller comprised of circuitry configured to execute a diagnosis module into which a signal of the in-cylinder pressure sensor is inputted and configured to diagnose a failure of the sensor based on the signal. The diagnosis module includes a reading module configured to read the signals of the in-cylinder pressure sensor at a first timing that is a timing retarded by a specific crank angle from a compression top dead center, and at a second timing that is a timing advanced by the specific crank angle from the compression top dead center, and a failure determining module configured to determine that the in-cylinder pressure sensor has failed when the failure determining module determines that a difference between signal values at the first timing and at the second timing exceeds a predefined threshold.

Disclosed is a method for diagnosis of an oxygen probe for a combustion engine, with the steps: When an engine's fuel injection is inactive, measuring the output electric voltage from the oxygen probe; If the measured output electrical voltage of the oxygen probe is greater than a predetermined minimum voltage threshold, measuring a pressure prevailing in an intake distributor of the engine; If the measured pressure in the intake distributor is less than a predetermined minimum pressure threshold, increasing the pressure to a value greater than the predetermined minimum pressure threshold; Determining the time period between the time when the output electrical voltage of the probe falls below a second predetermined voltage threshold and the time when the output electrical voltage of the probe falls below a third predetermined voltage threshold; and diagnosing the oxygen probe depending on elapsed the time period.

A method of continuously variable valve duration (CVVD) location learning may include when current position information applied to valve duration control in a CVVD system is not detected by a controller, executing a re-learning mode in which re-learning of short duration and long duration is performed by classifying a situation, in which the current position information is not detected, into a plurality of non-detection situations.

A method for predicting failure in a cylinder of a multi-cylinder engine is provided. Each cylinder has an associated pressure sensor to provide a signal indicative of pressure in the cylinder. The method includes identifying whether there is a non-fueling interval associated with any of the cylinder on the engine. The method includes determining at least one of parameters such as an indicated mean effective pressure, a peak cylinder pressure, a total heat released, or a total duration of heat released over a combustion cycle for the cylinder. The method includes comparing the at least one of the parameters with predefined threshold value, determining whether any of the parameters exceeds the predefined threshold value, and generating a signal indicating the impending cylinder failure if at least one of the parameters exceeds the corresponding predefined threshold value.

Disclosed are a method and apparatus for diagnosing a fault in a CVVD system. The method includes collecting information necessary to determine whether a fault diagnosis mode entry condition of the CVVD system is satisfied, determining whether the fault diagnosis mode entry condition is satisfied based on the collected information, calculating prediction duration corresponding to a current engine RPM and manifold pressure when the fault diagnosis mode entry condition is satisfied, calculating current duration based on an output value of a motor sensor for detecting the RPM of the duration control motor of the CVVD system, comparing the manifold pressure-based prediction duration D1 with the sensor output-based duration D2, and determining an error of the motor sensor or whether the CVVD system has failed by comparing a duration difference cumulative value, that is, a cumulative value of difference values between the D1 and D2, with a previously stored threshold.

An internal combustion engine-based system includes an internal combustion engine. The internal combustion engine-based system includes an engine interrupt connected to the engine. The engine interrupt is configured to selectively stop the operation of the engine. The internal combustion engine-based system includes a controller in communication with the engine interrupt. The internal combustion engine-based system includes a carbon monoxide detector in communication with the controller. The controller uses the engine interrupt to stop the operation of the engine when the carbon monoxide detector provides the controller with signals that are representative of a carbon monoxide level proximate the internal combustion engine that together form a trend of building carbon monoxide amounts over a set time interval.

According to one or more embodiments of the technical solutions described herein, a control system in a motor vehicle that includes an internal combustion engine includes an oxygen sensor, and an oxygen sensor diagnosis module to diagnose the oxygen sensor. The oxygen sensor diagnosis includes performing an intrusive rich-to-lean diagnostic for the oxygen sensor, and detecting a lean-to-rich diagnostic event. In response, the diagnosis includes performing a passive lean-to-rich diagnostic for the oxygen sensor, the lean-to-rich diagnostic event comprising a fuel enrichment.

Various embodiments include a method comprising: moving a piston toward TDC in successive pump cycles; during the movement, closing an inlet valve by applying current to an electromagnet; generating a pressure signal downstream of the outlet; applying a measurement current to the electromagnet when the inlet valve is closed; while the piston moves away from TDC, detecting an opening position at which an opening movement of the inlet valve begins on the basis of a predetermined change with respect to time of the measurement current; checking whether a value sequence of the ascertained opening positions over multiple pump cycles satisfies a predetermined discrepancy criterion with regard to the sensor signal; and if the discrepancy criterion is satisfied, generating a fault signal relating to the pressure sensor.

The present teaching aims to provide: a cam angle sensor fault diagnosis apparatus for straddled vehicle, capable of detecting a fault of a cam angle sensor installed in a straddled vehicle and guessing a fault place; an engine system; and a straddled vehicle. A cam angle sensor fault diagnosis apparatus for straddled vehicle includes: a cam signal receiving unit connected to a signal output line through which a cam angle sensor outputs a cam signal in accordance with the rotation angle, the cam signal receiving unit being configured to receive a cam signal via the signal output line; a state determination unit that determines one or two fault states of the cam angle sensor from a disconnection state, a power supply fault state, and a ground fault state, distinguishably from the other fault states, in accordance with a signal level of a cam signal received by the cam signal receiving unit; and a signal output unit that outputs a fault signal representing the one or two fault states determined by the state determination unit, in such a manner that the fault signal representing the one or two fault states is different from a fault signal representing the other fault states.

An Engine Control Unit (ECU) for adapting to irregularities in a trigger wheel includes a memory element that stores a table with data of dimensions of the trigger wheel. The ECU is configured to (i) use a position sensor to detect a tooth and a corresponding tooth number, and (ii) set a time range for detection of a subsequent tooth with reference to the data in the memory element. The ECU is further configured to (iii) prevent errors due to irregularities in the trigger wheel in order to reinforce the ECU or an Engine Position Management System (EPMS) by adapting to a profile of each tooth of the trigger wheel, and in order to avoid an error in a plausibility check of the position sensor due to irregularities in the trigger wheel.