Abstract: An approach is provided for compensating engine fueling during starting conditions in which positive valve overlap is enabled early in the start. In one example, the valve timing is adjusted to increase positive overlap during cold starting conditions, and fuel adjustments are provided to compensate for the evaporation effects of the increased residual push-back.

Abstract: A system, comprising of an internal combustion engine having a combustion chamber with a piston located therein, an intake passage coupled to the combustion chamber, wherein the intake passage supplies intake air to the combustion chamber, an adjustable compressor arranged in the intake passage upstream of the combustion chamber, a throttle arranged in the intake passage upstream of the compressor, and a controller configured to operate the engine so that, at least under some conditions, the piston compresses an air and fuel mixture within the combustion chamber to attain substantial auto-ignition of the mixture; and to increase a boosting of the compressor to increase heating of the intake air, and to decrease the boosting to decrease heating of the intake air, while throttling the intake air with the throttle.

Abstract: A method for controlling valve timing for and engine having adjustable valve timing is presented. In one embodiment, the method allows the intake valve timing to be controlled with respect to exhaust valve timing or the method allows the exhaust valve timing to be controlled with respect to intake valve timing. In addition, the method can bound valve overlap between upper and lower limits so that engine emissions and fuel economy may be improved.

Abstract: A method for controlling valve timing for and engine having adjustable valve timing is presented. In one embodiment, the method allows the intake valve timing to be controlled with respect to exhaust valve timing or the method allows the exhaust valve timing to be controlled with respect to intake valve timing. In addition, the method can bound valve overlap between upper and lower limits so that engine emissions and fuel economy may be improved.

Abstract: An approach is provided for compensating engine fueling during starting conditions in which positive valve overlap is enabled early in the start. In one example, the valve timing is adjusted to increase positive overlap during cold starting conditions, and fuel adjustments are provided to compensate for the evaporation effects of the increased residual push-back.

Abstract: A system, comprising of an internal combustion engine having a combustion chamber with a piston located therein, an intake passage coupled to the combustion chamber, wherein the intake passage supplies intake air to the combustion chamber, an adjustable compressor arranged in the intake passage upstream of the combustion chamber, a throttle arranged in the intake passage upstream of the compressor, and a controller configured to operate the engine so that, at least under some conditions, the piston compresses an air and fuel mixture within the combustion chamber to attain substantial auto-ignition of the mixture; and to increase a boosting of the compressor to increase heating of the intake air, and to decrease the boosting to decrease heating of the intake air, while throttling the intake air with the throttle.

Abstract: A system comprising of an engine having a first group of cylinders and a second group of cylinders, a first variable valve system in said first group, a second variable valve system in said second group, and a controller for determining degradation of operation of at least one of said first and second variable valve systems, said controller determining said degradation in response to controller errors of said valves and differences between operation of said first and second valve systems.

Abstract: A system comprising of an engine having a first group of cylinders and a second group of cylinders, a first variable valve system in said first group, a second variable valve system in said second group, and a controller for determining degradation of operation of at least one of said first and second variable valve systems, said controller determining said degradation in response to controller errors of said valves and differences between operation of said first and second valve systems.