A method and a system for determining a temperature for pressurized fuel included in a high pressure fuel system arranged for providing fuel to an engine are presented. The method includes determining a first temperature for a first fuel volume included in a first section of the high pressure fuel system, where the first section includes a common rail fuel system. The method further includes determining a second temperature for a second fuel volume included in a second section of the high pressure fuel system, where the second section includes at least one fuel injector arranged in a cylinder head of the engine. The method also includes the step of determining the temperature for the pressurized fuel based at least on the first temperature and on the second temperature.

A fuel injection control method of injecting fuel to a combustion chamber through an injector, the method may include performing, by a controller electrically-connected to the injector, a main injection configured of controlling the injector to inject the fuel in a target injection fuel amount; and performing, by the controller, a pre-injection configured of driving the injector to inject the fuel in advance, before the performing of the main injection with a predetermined idle time interposed therebetween, wherein the performing of the pre-injection is configured of magnetizing an injector coil of the injector by applying a current to the injector during a predetermined pre-injection time, in which a flow rate of the fuel is prevented from being generated by the pre-injection.

A fuel injection control method of injecting fuel to a combustion chamber through an injector, the method may include performing, by a controller electrically-connected to the injector, a main injection configured of controlling the injector to inject the fuel in a target injection fuel amount; and performing, by the controller, a pre-injection configured of driving the injector to inject the fuel in advance, before the performing of the main injection with a predetermined idle time interposed therebetween, wherein the performing of the pre-injection is configured of magnetizing an injector coil of the injector by applying a current to the injector during a predetermined pre-injection time, in which a flow rate of the fuel is prevented from being generated by the pre-injection.

Electronic fuel injection for an internal combustion engine maintains an operator-specified air-to-fuel ratio during engine operations in high-speed, high-volume, mixed fuel applications. A microprocessor-based controller executes a program stored in memory to calculate a fuel flow value as a function of the specified air-to-fuel ratio and specified density ratio of mixed fuels. The controller outputs a control signal to a variable fuel flow relief valve and receives feedback from an engine fuel flow sensor. The controller adjusts the control signal until the feedback matches the fuel flow value. The program optimizes the fuel flow value by accounting for engine air flow, water vapor density, and dry air density effects in the calculation, based on signals received by the controller from various environmental sensors. The system has particular application in dragster engines that burn a mixture of nitromethane and methanol.

Electronic fuel injection for an internal combustion engine maintains an operator-specified air-to-fuel ratio during engine operations in high-speed, high-volume, mixed fuel applications. A microprocessor-based controller executes a program stored in memory to calculate a fuel flow value as a function of the specified air-to-fuel ratio and specified density ratio of mixed fuels. The controller outputs a control signal to a variable fuel flow relief valve and receives feedback from an engine fuel flow sensor. The controller adjusts the control signal until the feedback matches the fuel flow value. The program optimizes the fuel flow value by accounting for engine air flow, water vapor density, and dry air density effects in the calculation, based on signals received by the controller from various environmental sensors. The system has particular application in dragster engines that burn a mixture of nitromethane and methanol.

Disclosed is a method for the diagnosis of a digital valve in a fuel injection system. In the diagnosis, a diagnosis current is applied to the digital valve with an intensity and for a hold time that are predetermined by experiment on digital valves identified as being fault-free, this intensity and this time being recognized as being sufficient for an inflection on a curve of the closing current to be detected in the hold time. Measurements are taken at more than 3 kHz of the diagnosis current added to the induced current in the hold time. When an inflection on the current curve is detected in this hold time, it is concluded that the valve is working correctly. When no inflection on the curve is detected in this hold time, it is concluded that the valve is faulty.

A method and system for correcting a fuel injection amount that injects fuel may include applying a current value for injecting a target fuel amount and injecting fuel under a driving condition in which fuel injection is blocked; determining a frequency analysis value for a pressure signal of the fuel pressure rail when the fuel is injected; determining a fuel amount difference corresponding to a difference value between the frequency analysis value and a reference frequency analysis value stored in a data storage in advance; and correcting a current value of the injector which is applied to inject the target fuel amount to remove the fuel amount difference.

A method and system for cleaning a fuel nozzle during engine operation is provided. Operations include operating the compressor section to provide the flow of oxidizer at a first oxidizer flow condition to the combustion chamber, wherein the first oxidizer flow condition comprises an environmental parameter; operating the fuel system at a first fuel flow condition to produce a fuel-oxidizer ratio at the combustion chamber; comparing the environmental parameter to a first environmental parameter threshold; and transitioning the fuel system to a second fuel flow condition corresponding to a cleaning condition at the fuel nozzle if the environmental parameter is equal to or greater than the first environmental threshold.

Electronic fuel injection for an internal combustion engine maintains an operator-specified air-to-fuel ratio during engine operations in high-speed, high-volume, mixed fuel applications. A microprocessor-based controller executes a program stored in memory to calculate a fuel flow value as a function of the specified air-to-fuel ratio and specified density ratio of mixed fuels. The controller outputs a control signal to a variable fuel flow relief valve and receives feedback from an engine fuel flow sensor. The controller adjusts the control signal until the feedback matches the fuel flow value. The program optimizes the fuel flow value by accounting for engine air flow, water vapor density, and dry air density effects in the calculation, based on signals received by the controller from various environmental sensors. The system has particular application in dragster engines that burn a mixture of nitromethane and methanol.

Electronic fuel injection for an internal combustion engine maintains an operator-specified air-to-fuel ratio during engine operations in high-speed, high-volume, mixed fuel applications. A microprocessor-based controller executes a program stored in memory to calculate a fuel flow value as a function of the specified air-to-fuel ratio and specified density ratio of mixed fuels. The controller outputs a control signal to a variable fuel flow relief valve and receives feedback from an engine fuel flow sensor. The controller adjusts the control signal until the feedback matches the fuel flow value. The program optimizes the fuel flow value by accounting for engine air flow, water vapor density, and dry air density effects in the calculation, based on signals received by the controller from various environmental sensors. The system has particular application in dragster engines that burn a mixture of nitromethane and methanol.