Disclosed is a method for diagnosing sealing in a fuel vapor recirculation system for an engine of a motor vehicle. An electronic module is integrated into the engine control unit that is woken up and placed on standby periodically while the engine is off, at the start and end of time intervals in order to perform a respective leak diagnosis, the fuel vapor temperature Tsys being estimated as a function of a time t ending at the start of each interval and starting when the engine is switched off according to the following equation, in which Tamb is the ambient temperature measured, Tsys0 is the fuel vapor temperature when the vehicle is switched off, and tsys is a system response time:

Tsys(t)=Tamb+(Tsys0−Tamb)e.sup.−t/tsys.

Various embodiments include a method for checking a sensor for soot particles in exhaust of an engine comprising: generating a sensor current between a first electrode and a second electrode of the sensor, wherein the first electrode and the second electrode define a gap through which the exhaust gas flows between the electrodes, by applying a difference in potential between the electrodes, wherein soot particles accumulate on the electrodes and, after a dwell time dependent on the preloading of the electrodes with soot particles, they move from a first electrode to the respective second electrode generating a flow of current as a measure of the quantity of soot in the stream of exhaust gas; determining whether a peak in the sensor current is measured after the switching off of the internal combustion engine; and if no peak in the sensor current is measured, flagging the particle sensor as faulty.

A method for operating an internal combustion engine having a cylinder, an intake valve, an air pipe, and a valve element disposed in the air pipe, includes detecting a signal for causing a fuel supply of the cylinder to switch off. The valve element is moved out of a first position into a second position triggering a lower flow cross-section while the fuel supply is still activated, where a first cam for actuating the intake valve is allocated to the intake valve. While the fuel supply is still activated, switching from the first cam to a second cam and via the second cam the intake valve is actuated such that the intake valve causes a reduced air intake. An exhaust cam shaft for actuating an exhaust valve is set in an advance direction such that a valve intersection of the intake valve and of the exhaust valve ceases.

A control method for an internal combustion engine in which a driving force is transmitted through a clutch to a driving wheel of a vehicle, the control method includes: when the internal combustion engine which is automatically stopped in a state where the clutch is disengaged is restarted, performing a torque down control to decrease a target torque of the internal combustion engine when the clutch is engaged; and setting a target torque in the torque down control, to a predetermined torque lower limit value determined in accordance with a driving state, the torque lower limit value including at least one of a predetermined full open value set when an accelerator opening degree is full open, and a predetermined full close value set when the accelerator opening degree is full close.

In some embodiments of the present disclosure, sensors mounted on a vehicle can allow opportunities for coasting to be predicted based on environmental conditions, route planning information, and/or vehicle-to-vehicle or vehicle-to-infrastructure signaling. In some embodiments of the present disclosure, these sensors can also predict a need for power and/or an end of a coast opportunity. These predictions can allow the vehicle to automatically enter a coasting state, and can predictively re-engage the engine and/or powertrain in order to make power available with no delay when desired by the operator.

A control device for a multi-stage automatic transmission-equipped vehicle includes a hydraulic power controller, a combustion controller configured to, if a predetermined combustion stop condition is satisfied when the vehicle is traveling, perform deceleration-period combustion stop control, and limit combustion restart triggered by a reduction in rotational speed of an internal combustion engine, during execution of the deceleration-period combustion stop control, and a motoring controller configured to control the rotational drive of the internal combustion engine by a motor during execution of the deceleration-period combustion stop control so that the rotational speed of the internal combustion engine is maintained at a predetermined rotational speed during a period of time from the time that the rotational speed of the internal combustion engine decreases to the predetermined rotational speed until downshifting to a predetermined gear ratio is completed.

Provided is a marine engine, including: an air controller configured to supply compressed air to a combustion chamber in an upstroke of a piston after a crash astern signal is output; a fuel controller configured to stop supply of fuel to the combustion chamber when the crash astern signal is output, and to resume the supply of the fuel after a backward rotation of a crankshaft; and a compression ratio controller configured to move a top dead center position of the piston toward an opposite side of a bottom dead center position of the piston when the crash astern signal is output, and the top dead center position of the piston is on the bottom dead center position side with respect to a predetermined position set in advance.

Systems and methods for determining operation of a cylinder deactivating/reactivating device are disclosed. In one example, a warm engine is rotated without being supplied fuel to determine the presence or absence of valve actuator degradation. Degraded valve actuators may be determined when there is a lack of a temperature rise in the engine exhaust system.

A carbon monoxide shutoff system for an engine of a portable electrical generator has a carbon monoxide gas sensor, a microcontroller, and an output indicator. The carbon monoxide gas sensor generates an output electrical current proportional to a detected concentration of ambient carbon monoxide. The microcontroller has an input connected to the carbon monoxide gas sensor, and an output connected to an operational control of the engine. A deactivation signal generated by the microcontroller in response to detection of a deactivation condition is based upon the output electrical current from the carbon monoxide gas sensor matching predefined value and duration thresholds. The deactivation signal is operative to stop the engine.

A method of controlling a hybrid electric vehicle is provided. The method includes determining whether a condition for turning off an engine is satisfied and determining engine clutch disengaging time and residual purge gas consuming time from engine driving status information when the condition is satisfied. Engine clutch-engaged charging control time is determined from the engine clutch disengaging time and the residual purge gas consuming time. The method includes closing a purge control solenoid valve and starting to perform engine clutch-engaged charging control. The engine clutch-engaged charging control is maintained for the determined engine clutch-engaged charging control time and then engine clutch disengaging control is performed for the determined engine clutch disengaging time. The engine is stopped after the engine clutch disengaging control is performed.