Methods and systems are provided for improving engine spark and torque control. In one example, adaptive spark control of an engine may include a modifier that adjusts the inferred fuel octane estimate and a spark adaptation based on ambient humidity. The method allows the speed-load dependent variation in octane effect of humidity to be reduced.

A fuel tank containing a fuel and oil mixture is managed to determine if the fuel and oil mixture contains the correct ratio for a motor. The fuel tank containing a fuel and oil mixture is monitored. A fuel to oil ratio is selected for the motor. A combined viscosity of the fuel and oil mixture is calculated with respect to the fuel to oil ratio, and the temperature of the fuel and oil mixture. The combined viscosity is used to determine a predetermined range of the combined viscosity. The viscosity of the fuel and oil mixture within the fuel tank is measured as a measured viscosity. If the measured viscosity of the fuel and oil mixture does not correspond with the predetermined range, then a user may be alerted that the measured viscosity does not correspond with the predetermined range.

A fuel tank containing a fuel and oil mixture is managed to determine if the fuel and oil mixture contains the correct ratio for a motor. The fuel tank containing a fuel and oil mixture is monitored. A fuel to oil ratio is selected for the motor. A combined viscosity of the fuel and oil mixture is calculated with respect to the fuel to oil ratio, and the temperature of the fuel and oil mixture. The combined viscosity is used to determine a predetermined range of the combined viscosity. The viscosity of the fuel and oil mixture within the fuel tank is measured as a measured viscosity. If the measured viscosity of the fuel and oil mixture does not correspond with the predetermined range, then a user may be alerted that the measured viscosity does not correspond with the predetermined range.

A fuel tank containing a fuel and oil mixture is managed to determine if the fuel and oil mixture contains the correct ratio for a motor. The fuel tank containing a fuel and oil mixture is monitored. A fuel to oil ratio is selected for the motor. A combined viscosity of the fuel and oil mixture is calculated with respect to the fuel to oil ratio, and the temperature of the fuel and oil mixture. The combined viscosity is used to determine a predetermined range of the combined viscosity. The viscosity of the fuel and oil mixture within the fuel tank is measured as a measured viscosity. If the measured viscosity of the fuel and oil mixture does not correspond with the predetermined range, then a user may be alerted that the measured viscosity does not correspond with the predetermined range.

A fuel tank containing a fuel and oil mixture is managed to determine if the fuel and oil mixture contains the correct ratio for a motor. The fuel tank containing a fuel and oil mixture is monitored. A fuel to oil ratio is selected for the motor. A combined viscosity of the fuel and oil mixture is calculated with respect to the fuel to oil ratio, and the temperature of the fuel and oil mixture. The combined viscosity is used to determine a predetermined range of the combined viscosity. The viscosity of the fuel and oil mixture within the fuel tank is measured as a measured viscosity. If the measured viscosity of the fuel and oil mixture does not correspond with the predetermined range, then a user may be alerted that the measured viscosity does not correspond with the predetermined range.

Methods and systems are provided for adjusting engine operation of a hybrid vehicle to increase power output, and fuel efficiency. In one example, a method may include operating the engine using an Atkinson cycle during a lower than threshold engine torque demand, and a lower than threshold battery state of charge, and operating the engine using an Otto cycle during a higher than threshold torque demand. During operating in the Otto cycle, an octane booster may be injected to the fuel line to increase the octane level in the fuel.

The present disclosure relates to a miniaturized fuel laboratory system having exterior dimensions enabling the system to be at least one of hand-holdable or contained on a component. The system makes use of a processor, a fuel inlet port for receiving a quantity of fuel to be used as a fuel test sample, and at least one fuel sensor in communication with the fuel inlet port for receiving the fuel test sample. The processor uses the information obtained by the fuel sensor to determine at least one characteristic of the fuel test sample.

Low-reactivity fuel such as gasoline is provided to a diesel engine cylinder sufficiently early in the injection stroke that it will be premixed. High reactivity fuel such as diesel fuel is then injected during the compression stroke, preferably around 40-60 before Top Dead Center (TDC), to provide a stratified distribution of fuel reactivity within the cylinder, one which provides ignition (the start of main heat release) at or near TDC, preferably at 0-10 prior to TDC. At that time, the low-reactivity fuel is again injected and burns in a diffusion-controlled manner owing to its lower reactivity, thereby providing greater power output (and thus increased load) with little or no increase in peak heat release rate (PHRR) and combustion noise.

A fuel separation system includes a fuel separator configured to receive a fuel stream and separate the fuel stream, based on a volatility of the fuel stream, into a vapor stream defined by a first auto-ignition characteristic value and a first liquid stream defined by a second auto-ignition characteristic value, the second auto-ignition characteristic value greater than the first auto-ignition characteristic value; and a heat exchanger fluidly coupled between a fuel input of the fuel stream and the fuel separator, the heat exchanger configured to transfer heat from the vapor stream to the fuel stream, and output a heated fuel stream to the fuel separator and a second liquid stream defined by the first auto-ignition characteristic value.

Methods and systems are provided for a fuel supply system for an internal combustion engine system, in particular of a motor vehicle, having at least one liquefied petroleum gas (LPG) tank for storing an LPG fuel and at least one direct injection unit, which has a direct injection fuel distributor and direct injection valves that can be supplied with fuel via said distributor. In order to improve supply of the internal combustion engine system with LPG fuel, the fuel supply system includes a booster pump inserted between the LPG tank and the direct injection fuel distributor. A discharge side of the booster pump is connected directly to the direct injection fuel distributor by at least one line, and the direct injection valves each have a closure part that rises outward from a valve seat to open the respective direct injection valve.