Fuel management system for efficient operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder of the engine. A fuel management microprocessor system controls injection of the anti-knock agent so as to control knock and minimize that amount of the anti-knock agent that is used in a drive cycle. It is preferred that the anti-knock agent is ethanol. The use of ethanol can be further minimized by injection in a non-uniform manner within a cylinder. The ethanol injection suppresses knock so that higher compression ratio and/or engine downsizing from increased turbocharging or supercharging can be used to increase the efficiency or the engine.

Fuel management system for efficient operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder of the engine. A fuel management microprocessor system controls injection of the anti-knock agent so as to control knock and minimize that amount of the anti-knock agent that is used in a drive cycle. It is preferred that the anti-knock agent is ethanol. The use of ethanol can be further minimized by injection in a non-uniform manner within a cylinder. The ethanol injection suppresses knock so that higher compression ratio and/or engine downsizing from increased turbocharging or supercharging can be used to increase the efficiency or the engine.

Fuel management system for efficient operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder of the engine. A fuel management microprocessor system controls injection of the anti-knock agent so as to control knock and minimize that amount of the anti-knock agent that is used in a drive cycle. It is preferred that the anti-knock agent is ethanol. The use of ethanol can be further minimized by injection in a non-uniform manner within a cylinder. The ethanol injection suppresses knock so that higher compression ratio and/or engine downsizing from increased turbocharging or supercharging can be used to increase the efficiency or the engine.

Fuel management system for efficient operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder of the engine. A fuel management microprocessor system controls injection of the anti-knock agent so as to control knock and minimize that amount of the anti-knock agent that is used in a drive cycle. It is preferred that the anti-knock agent is ethanol. The use of ethanol can be further minimized by injection in a non-uniform manner within a cylinder. The ethanol injection suppresses knock so that higher compression ratio and/or engine downsizing from increased turbocharging or supercharging can be used to increase the efficiency or the engine.

Methods and systems are providing for improving zero flow lubrication (ZFL) of a high pressure fuel pump coupled to direct fuel injectors via a direct injection fuel rail. A ZFL transfer function for the fuel pump is learned while fuel is at non-nominal fuel bulk modulus conditions and corrected for variations from a nominal fuel bulk modulus estimate. When zero flow lubrication of the pump is requested, the pump is operated with a duty cycle based on the learned transfer function and an instantaneous estimate of the fuel bulk modulus to compensate for differences in fuel condition from the nominal fuel bulk modulus estimate.

An internal combustion engine includes one main combustion chamber for the combustion of a first combustion mixture, one pre-combustion chamber for each respective main combustion chamber for the combustion of a second combustion mixture, a first fuel gas mixer for providing the first combustion mixture, a second fuel gas mixer for providing the second combustion mixture, an air feed line and a synthesis gas feed line, a first mixture line connected to the first fuel gas mixer and the main combustion chamber, and a second mixture line connected to the second fuel gas mixer and the pre-combustion chamber. The first fuel gas mixer is connected to the synthesis gas feed line for the admixing of synthesis gas, and an open or closed loop control device is provided for open or closed loop controlling mixing ratios of fuel, air and synthesis gas in the first combustion mixture and/or second combustion mixture.

Methods of operation of liquid and gaseous multi-fuel compression ignition engines that may be operated on a gaseous fuel or a liquid fuel, or a combination of both a gaseous fuel and a liquid fuel at the same time and in some embodiments, in the same combustion event. Various embodiments are disclosed.

It is an object of the invention to provide an at of realizing good combustion by lowering a combustion critical temperature below a temperature of intake air sucked into a cylinder, in the case where a first fuel that is difficult to ignite and a second fuel that is easy to ignite are supplied into the cylinder. The invention is a control device for an internal combustion engine that includes a control unit that supplies a first fuel that is difficult to ignite and a second fuel that is easy to ignite into a cylinder, and burns the first fuel that is difficult to ignite as well by igniting the second fuel that is easy to ignite, wherein the control unit carries out at least one of a reduction in a supply amount of the first fuel that is difficult to ignite and an increase in a supply amount of the second fuel that is easy to ignite, if a temperature of intake air sucked into the cylinder falls below a combustion critical temperature.