An object is to achieve stable diesel combustion and improvement in the thermal efficiency of the diesel combustion in an internal combustion engine using a fuel having a relatively high self-ignition temperature. A control apparatus for an internal combustion engine includes a fuel injection valve capable of injecting fuel into a combustion chamber and an ignition device whose position relative to the fuel injection valve is set in such a way that it can ignite fuel spray directly. The apparatus performs pre-injection at a predetermined pre-injection time during the compression stroke and main injection at a predetermined injection start time after pre-spray formed by the pre-injection is ignited by the ignition device, thereby causing self-ignition to occur and causing at least a portion of the main-injected fuel to burn by diffusion combustion. When the quantity of the pre-injected fuel is increased, the pre-injection time is advanced responsive to the increase in the quantity of the pre-injected fuel.

A method includes receiving a signal indicative of a change in an air-fuel ratio (AFR) for a mixture of air and fuel entering a first combustion chamber of a combustion engine, advancing firing timing of the first combustion chamber, receiving, from a knock sensor, a knock signal indicating that the combustion engine has begun to knock, determining a knock margin of the first combustion chamber based on when the combustion engine begins to knock, and storing the knock margin as associated with the knock timing and the AFR.

In a spark-ignition internal combustion engine having multiple cylinders, successive segment time periods assigned to the individual cylinders during working strokes thereof, and subsequently irregular running values are determined from the segment time periods. In a predefined speed range of the engine, the irregular running values of the cylinders are compared with a predefined threshold, and suspected auto-ignition for a first cylinder is detected if the irregular running value of a second cylinder located before the first cylinder in terms of timing of the ignition sequence undershoots the threshold. Fuel to the first cylinder suspected of auto-ignition is interrupted for a predefined number of cycles, and the fuel interruption influence on the irregular running values of the second cylinder during the cycles is detected. The suspected auto-ignition of the first cylinder is either confirmed or rejected based on the irregular running values occurring at the second cylinder.

In a spark-ignition internal combustion engine having multiple cylinders, successive segment time periods assigned to the individual cylinders during working strokes thereof, and subsequently irregular running values are determined from the segment time periods. In a predefined speed range of the engine, the irregular running values of the cylinders are compared with a predefined threshold, and suspected auto-ignition for a first cylinder is detected if the irregular running value of a second cylinder located before the first cylinder in terms of timing of the ignition sequence undershoots the threshold. Fuel to the first cylinder suspected of auto-ignition is interrupted for a predefined number of cycles, and the fuel interruption influence on the irregular running values of the second cylinder during the cycles is detected. The suspected auto-ignition of the first cylinder is either confirmed or rejected based on the irregular running values occurring at the second cylinder.

An ECU of an engine performs control to keep a constant engine speed when a load factor is equal to or less than a predetermined value, and to reduce and correct the engine speed in accordance with an increase in the load factor when the load factor exceeds the predetermined value. The ECU is provided with a reference droop control correction amount calculation unit (36), a correction amount adjustment map storage unit, and a post-adjustment correction amount calculation unit (38). The reference droop control correction amount calculation unit (36) obtains an engine speed reference reduction correction amount NBD that is increased at a constant rate in accordance with the increase in the load factor from the predetermined value. The correction amount adjustment map storage unit stores, as a correction amount adjustment map (111), a subtraction factor that varies depending on the load factor. On the basis of the engine speed reference reduction correction amount NBD and the subtraction factor, the post-adjustment correction amount calculation unit (38) calculates an engine speed reduction correction amount ND as an amount by which the engine speed is reduced and corrected in accordance with the increase in the load factor when the load factor exceeds the predetermined value.

An ECU of an engine performs control to keep a constant engine speed when a load factor is equal to or less than a predetermined value, and to reduce and correct the engine speed in accordance with an increase in the load factor when the load factor exceeds the predetermined value. The ECU is provided with a reference droop control correction amount calculation unit (36), a correction amount adjustment map storage unit, and a post-adjustment correction amount calculation unit (38). The reference droop control correction amount calculation unit (36) obtains an engine speed reference reduction correction amount NBD that is increased at a constant rate in accordance with the increase in the load factor from the predetermined value. The correction amount adjustment map storage unit stores, as a correction amount adjustment map (111), a subtraction factor that varies depending on the load factor. On the basis of the engine speed reference reduction correction amount NBD and the subtraction factor, the post-adjustment correction amount calculation unit (38) calculates an engine speed reduction correction amount ND as an amount by which the engine speed is reduced and corrected in accordance with the increase in the load factor when the load factor exceeds the predetermined value.

The invention relates to a method for operating an internal combustion engine comprising: determining a first set point value of a volume of air to be taken into the combustion chamber of the internal combustion engine within one working cycle thereof by retrieving the first set point value from a first characteristic map stored in a memory device of an electronic computing device as a function of a current engine speed of the internal combustion engine and as a function of a torque to be provided by the internal combustion engine; and determining a second set point value by retrieving the second set point value from a second characteristic map stored in the memory device of the electronic computing device as a function of a current engine speed of the internal combustion engine and as a function of a current volume of air supplied to the combustion chamber.

The invention relates to a method for operating an internal combustion engine comprising: determining a first set point value of a volume of air to be taken into the combustion chamber of the internal combustion engine within one working cycle thereof by retrieving the first set point value from a first characteristic map stored in a memory device of an electronic computing device as a function of a current engine speed of the internal combustion engine and as a function of a torque to be provided by the internal combustion engine; and determining a second set point value by retrieving the second set point value from a second characteristic map stored in the memory device of the electronic computing device as a function of a current engine speed of the internal combustion engine and as a function of a current volume of air supplied to the combustion chamber.

A method of exhaust braking a vehicle includes determining a wheel slip ratio based on input from vehicle sensors. Based on a determination that the wheel slip ratio is unstable, the method further includes sending a command to reduce exhaust braking. Based on a determination that exhaust braking is reduced, the method further includes determining a change in wheel slip ratio over time based on input from the vehicle sensors. Based on a determination that the change in wheel slip ratio over time is stabilizing, the method further includes sending a command to increase exhaust braking.

A method of exhaust braking a vehicle includes determining a wheel slip ratio based on input from vehicle sensors. Based on a determination that the wheel slip ratio is unstable, the method further includes sending a command to reduce exhaust braking. Based on a determination that exhaust braking is reduced, the method further includes determining a change in wheel slip ratio over time based on input from the vehicle sensors. Based on a determination that the change in wheel slip ratio over time is stabilizing, the method further includes sending a command to increase exhaust braking.