Abstract:
A method for operating an engine in a vehicle, the engine having at least a cylinder, the method comprising generating engine braking torque to stop rotation of the engine in a desired range by opening and closing at least an electrically actuated valve of the cylinder more than once during a cycle of the cylinder.
Abstract:
A system and method for operating at least an intake and exhaust valve in a cylinder with a piston of an engine in a vehicle are described. In one aspect, the method comprises maintaining at least one of the intake and exhaust valves in a closed position during a period. Further, during said period where said at least one valve is in said closed position, the method may also include opening the other of the intake and exhaust valve, then closing the other of the intake and exhaust valve, and then opening the other of the intake and exhaust valve.
Abstract:
A system and method to control engine valve timing to during the start of an internal combustion engine. Valves that may be deactivated are controlled in a manner to reduce hydrocarbon emissions during the start of an internal combustion engine.
Abstract:
A method for improving engine intake manifold pressure control of an internal combustion engine is described. According to one aspect of the description, the manifold pressure may be controlled to reduce fuel consumption and engine emissions during at least some operating conditions.
Abstract:
A system and method to control engine valve timing so that an internal combustion engine may be quickly started. Electromechanical valves are controlled to allow an engine to start with reduced cranking time. The method controls intake and exhaust valves without an explicit four-stroke engine cycle during a start.
Abstract:
A method for controlling a vehicle engine having a plurality of cylinders is provided. The method comprises: during engine idling, advancing spark timing of at least one cylinder to before a peak torque timing, and retarding spark timing from the advanced timing toward the peak torque timing in response to decreased engine speed to maintain idling speed.
Abstract:
A method for controlling a vehicle engine having a plurality of cylinders and an electric motor configured to rotate the engine is provided. The method includes, during engine idling, advancing spark timing of at least one cylinder to substantially before a peak torque timing. The method further includes adjusting motor torque output of the electric motor to maintain engine idle speed.
Abstract:
A method of operating an engine for a vehicle having at least a first cylinder, the method comprising of operating the first cylinder to provide at least one of compression braking and expansion braking by holding one of an intake valve and an exhaust valve of the first cylinder closed while opening, closing, and opening the other of the intake valve and the exhaust valve during a cycle of the first cylinder and during a first vacuum level of an intake manifold upstream of the first cylinder; and operating the first cylinder to provide at least one of compression braking and expansion braking by operating both the intake valve and the exhaust valve of the first cylinder during a cycle of the first cylinder to allow at least some air to flow through the first cylinder during a second vacuum level of the intake manifold.
Abstract:
A method of transitioning a cylinder of an engine from a spark ignition mode to a homogeneous charge compression ignition mode, the cylinder having at least one electrically actuated intake valve and at least one exhaust valve, the method comprising of before a transition, operating the cylinder with at least some overlap between an opening event of the intake valve and an opening event of the exhaust valve in the spark ignition mode; in response to a transition request, operating the cylinder with at least some negative overlap between an opening event of the intake valve and an opening event of the exhaust valve, retarding the intake valve opening and closing timing by different amounts and retarding ignition timing; and further increasing negative overlap and performing the homogeneous charge compression ignition mode.
Abstract:
A method of operating an engine having at least one cylinder including an intake valve and an exhaust valve, the method comprising of injecting a first amount of fuel into the cylinder; auto-igniting a first mixture of air and said first amount of fuel by compressing said first mixture; injecting a second amount of fuel into the cylinder after auto-igniting said first mixture; combusting a second mixture of said second amount of fuel and gasses from auto-ignition of said first mixture; holding an intake valve of the cylinder closed between auto-igniting the first mixture and combusting the second mixture; and exhausting said combusted second mixture.