A vehicular propulsion system, a vehicular fuel system and a method of operating an internal combustion engine. A separation unit that makes up a part of the fuel system may selectively receive and separate at least a portion of onboard fuel and a flowable adsorbent in order to separate the fuel into octane-enhanced and cetane-enhanced fuel components. A controller may be used to determine a particular operating condition of the internal combustion engine such that the onboard fuel can be sent to one or more combustion chambers within the internal combustion engine without first passing through the separation unit during one operating condition, or instead to the separation unit in situations where the internal combustion engine may require an octane-rich or cetane-rich mixture in another operating condition.

A returnless fuel system includes a fuel injector, an accumulator, a first fuel pump assembly and a second fuel pump assembly. The accumulator is adapted to store pressurized fuel that is utilized by the fuel injector during prescribed conditions. The first fuel pump assembly is adapted to supply the pressurized fuel at a controlled pressure to the fuel injector. The second fuel pump assembly is in fluid communication with the accumulator and the first fuel pump assembly, and is adapted to provide the pressurized fuel at a controlled pressure to the first fuel pump assembly and the accumulator.

A controller according to the present disclosure, in each combustion cycle that composes a change cycle, calculates the average .sub.n of control amounts from the first combustion cycle to the nth (1<=n<=N) combustion cycle and calculates the error .sub.n-.sub.o of the average .sub.n with respect to the average .sub.o of a reference normal population. Also, the controller sets both a positive threshold Z.sub./2*.sub.o/n.sup.1/2 and a negative threshold Z.sub./2*.sub.o/n.sup.1/2 based on the standard error .sub.o/n.sup.1/2 of the reference normal population in the case where the number of data is n. Then, the controller chooses an operation amount to be changed from a plurality of operation amounts, based on a comparison between a series of the errors .sub.n-.sub.o and a series of the positive thresholds Z.sub./2*.sub.o/n.sup.1/2 and a comparison between the series of the errors .sub.n-.sub.o and a series of the negative thresholds Z.sub./2*.sub.o/n.sup.1/2.

A controller according to the present disclosure, in each combustion cycle that composes a change cycle, calculates the average .sub.n of control amounts from the first combustion cycle to the nth (1<=n<=N) combustion cycle and calculates the error .sub.n-.sub.o of the average .sub.n with respect to the average .sub.o of a reference normal population. Also, the controller sets both a positive threshold Z.sub./2*.sub.o/n.sup.1/2 and a negative threshold Z.sub./2*.sub.o/n.sup.1/2 based on the standard error .sub.o/n.sup.1/2 of the reference normal population in the case where the number of data is n. Then, the controller chooses an operation amount to be changed from a plurality of operation amounts, based on a comparison between a series of the errors .sub.n-.sub.o and a series of the positive thresholds Z.sub./2*.sub.o/n.sup.1/2 and a comparison between the series of the errors .sub.n-.sub.o and a series of the negative thresholds Z.sub./2*.sub.o/n.sup.1/2.

A fuel system for an internal combustion engine is provided, which comprises a first fuel tank, a fuel filter device, arranged between a low pressure pump operated by an electric motor and a high pressure pump, a first fuel conduit, through which the low pressure pump is arranged to supply fuel to the fuel filter device, and a control device, arranged in connection with an electric motor operating the low pressure pump. An overflow conduit is arranged in connection with a deaeration outlet, arranged in the fuel filter device and the first fuel tank, and the control device is arranged to control the electric motor, in such a way that the low pressure pump is active when the internal combustion engine is turned off for a limited period, whereby fuel may flow from the fuel filter device via the deaeration outlet and the overflow conduit, back to the first fuel tank.

Methods and systems are described for a fuel system in an engine comprising two lift pumps. One example method comprises deactivating one of a first lift pump and a second lift pump if fuel fill level in a common reservoir decreases below a threshold fill level, wherein the first lift pump and the second lift pump are positioned in the common reservoir. By deactivating one of the two lift pumps, the two lift pumps may be protected from degradation due to fuel starvation.

A vehicular liquid containment system including a tank, a pressure sensor arranged to detect a pressure in a vapor dome inside the tank, at least two thermistors configured to detect temperatures at a plurality of levels of the tank, and leak detection logic operatively connected to the pressure sensor and the thermistors. The leak detection logic is configured to: use a first thermistor of the thermistors to perform a first measurement indicative of a temperature in the vapor dome in the tank; estimate an expected pressure evolution in function of at least the first temperature measurement; monitor pressure sensed by the pressure sensor, determine whether the monitored pressure deviates from the expected pressure evolution, and generate a leak condition signal conditional on the determining.

An alarm system is used for a vehicle including a fuel pump and an engine. The alarm system includes a measuring device, a computing device and a warning device. The measuring device is used to read a current rotation speed of the engine and respectively measures a plurality of running times of a plurality of rotation speed values of the current rotation speed. The computing device calculates a plurality of consuming times of the fuel pump corresponding to the rotation speed values according to the running times of the rotation speed values, respectively. When an accumulating consuming time accumulated by the consuming times reaches a default critical value, the warning device generates a warning message.

Methods and systems for evaluating whether or not a fuel amount that is greater than a threshold has been release to an engine via fuel injectors when the fuel injectors are commanded off are presented. In one example, an oxygen sensor is activated and engine cranking is prevented until a pumping current of the oxygen sensor is proportionate to a concentration of oxygen sensed via the oxygen sensor so that released fuel may be observed during engine starting.

A transport refrigeration system having: a refrigerated cargo space (119); a refrigeration unit (22) in operative association with the refrigerated cargo space, the refrigeration unit providing conditioned air to the refrigerated cargo space; a first engine (150) configured to power the vehicle; a second engine (26) configured to power the refrigeration unit; a first plurality of fuel tanks (350) fluidly connected to first engine, the first plurality of fuel tanks configured to supply fuel to the first engine; a second plurality of fuel tanks (330) fluidly connected to second engine, the second plurality of fuel tanks configured to supply fuel to the second engine; and a single filling point (310) fluidly connected to the first plurality of fuel tanks and second plurality of fuel tanks. The single filling point (310) is configured to receive fuel.