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 driving-side rotating body that rotates synchronously with a crankshaft of an internal combustion engine, a driven-side rotating body that is allowed to rotate relative to the driven-side rotating body and that rotates integrally with a camshaft that opens and closes an intake valve, and a phase adjustment mechanism for setting a relative rotation phase of the driving-side rotating body and the driven-side rotating body using a driving force of an electric motor are included. The phase adjustment mechanism is configured to be able to execute retarding control for setting the relative rotation phase to the retarding side until reaching a phase in which the internal combustion engine cannot be started and autonomous running is not possible even if fuel injection and ignition are performed in the internal combustion engine.

A drive circuit is controlled when power is interrupted. When power is turned off, a main power supply is switched to a sub-power supply, and a residual charge of a step-up circuit is lowered to a drive voltage of a drive circuit using a step-down circuit is used as the sub-power supply.

Methods and systems for operating an engine with an electrically heated catalyst and an electrically driven compressor are described. In one example, the electrically driven compressor and the electrically heated catalyst are activated before an engine start so that vehicle emissions may be reduced more efficiently at engine starting and thereafter.

A method and system for operating a vehicle that includes an automatic transmission with a torque converter clutch is described. In one example, the method includes predicting a time that the torque converter clutch will open so that stopping rotation of the engine may be requested before the torque converter clutch is opened. The stopping rotation of the engine is requested to conserve fuel.

A method for detecting the physical stoppage of an internal combustion engine including a crankshaft that drives a toothed wheel having a plurality of teeth, each tooth corresponding to different angular positions of the crankshaft, a sensor positioned next to the toothed wheel generates a signal characteristic of the passage of a tooth. The method detects a tooth from the signal generated by the sensor, identifies the tooth detected, triggers a timeout, and detects stoppage of the engine if the passage of a tooth adjacent to the tooth detected has not been detected before the end of the timeout. The value of the timeout is dependent on the tooth identified, and including: determining crankshaft angular position depending on the tooth identified, the value of the timeout dependent on the angular position of the crankshaft, determining the preferential stopping positions of the crankshaft and assigning a first timeout value for the preferential stopping positions and assigning at least a second value for the other positions of the crankshaft. The first timeout value being less than the second timeout value.

A controller includes a soak timer, a nonvolatile memory, and a determining section. The determining section is configured to perform a rationality check on a condition that a performance condition is met. The determining section is also configured to make the performance condition strict when an obtained index value of a vehicle outside temperature, that is obtained when an elapsed amount of time reaches a specified amount of time, and the determining section is activated, is higher than a stored index value of the vehicle outside temperature stored in the nonvolatile memory.

The disclosure relates to a method and a device for checking the functionality of a crankcase ventilation system of an internal combustion engine. The crankcase ventilation system includes two crankcase ventilation lines arranged between a crankcase outlet of a crankcase and an associated introduction point into an air path of the internal combustion engine, via which crankcase ventilation lines gas can be introduced from the crankcase into the air path. The method includes measuring a pressure in the crankcase, supplying the measured pressure values to a control unit, and calculating the gradient of the measured pressure. The method also includes performing a gradient check, checking whether the gradient satisfies a specified criterion, and returning to the measurement of the pressure if the gradient satisfies the specified criterion. The method also includes recording an entry in a fault memory if the gradient does not satisfy the specified criterion.

An internal combustion engine (1) for a vehicle is equipped with a variable compression ratio mechanism (2) capable of changing the mechanical compression ratio. An idle stop, which is for automatically stopping the internal combustion engine (1) when the vehicle stops, and a sailing stop, which is for stopping the internal combustion engine (1) in conjunction with the release of a forward clutch (8) during inertial travel, are carried out. A target compression ratio during normal travel is set on the basis of the load and rotation speed of the internal combustion engine (1). During an idle stop the target compression ratio is set to an idle stop restart compression ratio (εis). During a sailing stop the target compression ratio is set to a sailing stop restart compression ratio (εss). The sailing stop restart compression ratio (εss) is lower than the idle stop restart compression ratio (εis).

Methods and systems are provided for an aftertreatment system. In one example, a system comprising a spark-ignited engine comprising a selective catalytic reduction device (SCR) arranged in an exhaust passage downstream of a catalyst, and an injector positioned to inject a reductant directly into the exhaust passage downstream of the catalyst subsequent an engine shut-off event.