A method for operating an internal combustion engine in an idle mode, in which an ignition angle and/or an air quantity of the internal combustion engine is influenced and/or is modified as a function of an idle rotation speed of the internal combustion engine. The ignition angle and/or the air quantity and/or a fuel quantity for at least one combustion chamber of the internal combustion engine is modified as a function of at least one variable characterizing a combustion event in the combustion chamber.

Methods and systems are provided for controlling a vehicle engine to deliver desired torque to a power take off device coupled to the engine. In one example, the method may include, learning a filtered PTO torque demand during vehicle acceleration, and steady state operation, and during transition in engine states using the learned PTO torque demand to adjust engine speed in order to deliver a desired engine torque output for optimal operation of the PTO device.

Methods and systems are provided for reducing a spark plug soot load and a combustion chamber soot load by controlling spark plug timing while injecting water or washer fluid. In one example, water or washer fluid is injected during a torque reduction while advancing spark timing so as to provide at least a portion of the torque reduction while opportunistically cleaning soot from the spark plug and combustion chamber. By reducing spark plug soot load, misfire occurrence is reduced, while pre-ignition occurrence is reduced by decarbonizing the combustion chamber.

Methods and systems are provided for reducing a spark plug soot load and a combustion chamber soot load by controlling spark plug timing while injecting water or washer fluid. In one example, water or washer fluid is injected during a torque reduction while advancing spark timing so as to provide at least a portion of the torque reduction while opportunistically cleaning soot from the spark plug and combustion chamber. By reducing spark plug soot load, misfire occurrence is reduced, while pre-ignition occurrence is reduced by decarbonizing the combustion chamber.

A method of controlling engine RPM in a marine propulsion device having an engine that effectuates rotation of a propulsor through a gear system that shifts amongst a forward gear position, a reverse gear position, and a neutral position, includes determining that a coolant temperature is below a temperature threshold or that a battery voltage is below a voltage threshold, and then increasing an engine RPM setpoint by a compensation RPM amount while the engines remains in an idle state in order to increase the coolant temperature or the battery voltage. When a shift instruction is detected to transition the gear system from the reverse gear position to the neutral position or from the forward gear position to the neutral position, the engine RPM setpoint is reduced by a shift RPM reduction amount during transition of the gear system, and the engine is controlled according to the engine RPM setpoint.

A method of controlling engine RPM in a marine propulsion device having an engine that effectuates rotation of a propulsor through a gear system that shifts amongst a forward gear position, a reverse gear position, and a neutral position, includes determining that a coolant temperature is below a temperature threshold or that a battery voltage is below a voltage threshold, and then increasing an engine RPM setpoint by a compensation RPM amount while the engines remains in an idle state in order to increase the coolant temperature or the battery voltage. When a shift instruction is detected to transition the gear system from the reverse gear position to the neutral position or from the forward gear position to the neutral position, the engine RPM setpoint is reduced by a shift RPM reduction amount during transition of the gear system, and the engine is controlled according to the engine RPM setpoint.

Methods and systems are provided for reducing idling torque imbalances between cylinders by actuating a common camshaft to which the cylinders are coupled. The camshaft may be adjusted within camshaft limits during each combustion event of each cylinder. In this way, idling NVH issues may be addressed.

Methods and systems are provided for reducing idling torque imbalances between cylinders by actuating a common camshaft to which the cylinders are coupled. The camshaft may be adjusted within camshaft limits during each combustion event of each cylinder. In this way, idling NVH issues may be addressed.

A method includes operating an engine system including a plurality of cylinders, a plurality of fuel injectors configured to provide fuel the plurality of cylinders, a compression braking system configured to selectably brake at least a first set of the plurality of cylinders, and an exhaust aftertreatment system including at least one catalyst. The method includes determining a condition for brake-fuel operation and, in response to the act of determining, operating the engine in a brake-fuel mode wherein the compression brake is actuated to provide compression braking of the first set of the plurality of cylinders and a second set of the plurality of cylinders receives and combust fuel provided from respective ones of the plurality of fuel injectors.

A method includes operating an engine system including a plurality of cylinders, a plurality of fuel injectors configured to provide fuel the plurality of cylinders, a compression braking system configured to selectably brake at least a first set of the plurality of cylinders, and an exhaust aftertreatment system including at least one catalyst. The method includes determining a condition for brake-fuel operation and, in response to the act of determining, operating the engine in a brake-fuel mode wherein the compression brake is actuated to provide compression braking of the first set of the plurality of cylinders and a second set of the plurality of cylinders receives and combust fuel provided from respective ones of the plurality of fuel injectors.