Method and systems are provided for, in response to a state of charge (SOC) of a vehicle battery increasing above a threshold SOC, reducing an alternator charging based on one or more of a spark timing, an engine speed, an air-fuel ratio, and an engine load. In this way, fuel consumption may be reduced while maintaining a battery SOC for operation of front-end accessories may be achieved, and fuel consumption may be reduced during aggressive vehicle driving conditions such has high engine loads near transmission downshift thresholds and high engine speeds.

A system includes an engine adapted to output a torque, a parasitic load adapted to receive a portion of the torque from the engine, and a controller communicably coupled to the parasitic load. The controller is configured to determine an actual exhaust temperature value of an exhaust gas flow exiting the engine and a minimum fuel amount to be injected into the engine. The controller is configured to compare the actual exhaust temperature value with an exhaust temperature threshold value of the exhaust gas flow to determine a first difference between the actual exhaust temperature value and the exhaust temperature threshold value. The controller is configured to determine a target torque output of the engine based on the first difference and the minimum fuel amount. The controller is configured to cause the torque to be increased to attain the target torque output using the parasitic load.

Disclosed is a method for controlling a speed of a vehicle combustion engine, the engine including at least one combustion chamber, into which a mixture of air and fuel is injected, and an air box, configured to inject the air into the combustion chamber and having an air flow rate controlled by a regulating butterfly valve, the regulating butterfly valve having a variable angular position, controlled by a predetermined position of an actuator. The method includes the steps of evaluating a so-called “load” resistant torque resulting from a plurality of external loads applied to the engine, determining, from the calculated load resistant torque, a position of the actuator, so as to determine an angular position of the regulating butterfly valve, and controlling the position of the actuator, so as to control the engine speed.

An engine control system controls a work machine including an engine, a fuel injection device that injects fuel into the engine, and a hydraulic pump that is driven by the engine. The rotation state amount specification unit specifies a rotation state amount related to rotation of the engine. The injection amount determination unit determines a fuel injection amount by the fuel injection device based on the rotation state amount.

In a test run, in order to easily provide a high-quality propulsion torque of a torque generator based on the partially low-quality measured variables available on the test bench, it is foreseen that an inner torque (M.sub.i) of the torque generator (D) is measured and based on the measured inner torque (M.sub.i), from an equation of motion, including the measured inner torque (M.sub.i), a dynamic torque (M.sub.dyn) and a shaft torque (M.sub.w) measured on the output shaft of the torque generator (D), a correction torque ({circumflex over (M)}.sub.cor) is estimated, and from the estimated correction torque ({circumflex over (M)}.sub.cor) and the measured inner torque (M.sub.i), the propulsion torque (M.sub.v) according to the relation M.sub.v={circumflex over (M)}.sub.cor+M.sub.i is computed.

A system and method for monitoring the negative impact of a filtration system on the fuel economy of an internal combustion engine. A filter monitoring controller receives engine operating parameters of the internal combustion engine. The filter monitoring controller determines an amount of power generated by the internal combustion engine based at least in part on the engine operating parameters. The filter monitoring controller determines a filter hydraulic power consumption of a filtration system providing a fluid to the internal combustion engine. The filter monitoring controller determines a fuel economy impact of the filtration system on the internal combustion engine based at least in part on the filter hydraulic power consumption of the filtration system. The filter monitoring controller compares the fuel economy impact of the filtration system to a threshold fuel economy impact to determine whether a filter element of the filtration system requires servicing.

Disclosed is a method for controlling a speed of a vehicle combustion engine, the engine including at least one combustion chamber, into which a mixture of air and fuel is injected, and an air box, configured to inject the air into the combustion chamber and having an air flow rate controlled by a regulating butterfly valve, the regulating butterfly valve having a variable angular position, controlled by a predetermined position of an actuator. The method includes the steps of evaluating a so-called “load” resistant torque resulting from a plurality of external loads applied to the engine, determining, from the calculated load resistant torque, a position of the actuator, so as to determine an angular position of the regulating butterfly valve, and controlling the position of the actuator, so as to control the engine speed.

Disclosed is a method for regulating the speed of an engine which drives a disengageable device. The regulation of the engine speed is effected in accordance with a first mode when the disengageable device is disengaged and in accordance with a second mode when the disengageable device is engaged. The determination is effected by: —estimating the resistive torque exerted on the engine by the disengageable device; —changing a binary value from a first value representative of the disengaged state to a second value representative of the engaged state when the estimated resistive torque is higher than a first predetermined threshold for a first predetermined period of time; and —changing the binary value from the second value to its first value when, for a second predetermined period of time, the estimated resistive torque is lower than a second threshold possibly equal to the first threshold.

Cross-port air flow that improves engine fuel economy and reduces pumping losses during part-throttle operation can be implemented in various types of internal combustion engine systems using ports that interconnect the intake ports of different cylinders, thus allowing different cylinders to share combustion air. Cross-port air flow is commenced during part-throttle engine operation to disrupt the primary combustion air flow from each throttle to its associated cylinder, which reduces charge density and engine power. The engine compensates for the reduced power by incrementally opening the throttles, thus increasing the primary combustion air flow, reducing pumping losses and improving fuel economy.

To provide a controller and a control method for internal combustion engine which can reduce arithmetic load, while suppressing deterioration in the estimation accuracy of the parameter relevant to the combustion state, even if the error component of high frequency is included in the crank angle acceleration. A controller for internal combustion engine, by referring an unburning condition data, calculates a shaft torque in unburning in the vicinity of the top dead center in the burning condition; calculates an external load torque based on calculated shaft torque in unburning and the actual shaft torque in burning in the vicinity of the top dead center; calculates a shaft torque in unburning by referring the unburning condition data; calculates an increment of gas pressure torque by burning based on the shaft torque in unburning, the actual shaft torque in burning, and the external load torque.