Various methods and systems are provided for health assessments of a fuel system. In one example, a fuel system includes a low-pressure pump operable to pump fuel from a fuel source at a first pressure, a high-pressure pump operable to increase the first pressure to a second pressure, a valve positioned between the low-pressure pump and the high-pressure pump and operable to control fuel flow to the high-pressure pump, a common fuel rail fluidly coupling the high-pressure pump to a plurality of fuel injectors coupled to cylinders of an engine, and a controller. The controller is operable to adjust an amount of valve electrical current supplied to the valve to reach a commanded pressure of the common fuel rail during cylinder firing conditions, the supplied valve electrical current adjusted based on a valve pre-firing correction factor for the valve obtained based on valve electrical current prior to cylinder firing commencing.

Methods and systems are provided for conducting a fuel tank diagnostic. In one example, a method comprises sealing a fuel tank of a vehicle, retrieving data related to fuel tank pressure from a crowd of vehicles, and indicating the fuel tank of the vehicle being diagnosed is degraded responsive to data related to fuel tank pressure from the crowd insufficiently correlating with a set of data related to fuel tank pressure from the vehicle. In this way, fuel tank degradation may be indicated without coupling the fuel tank of the vehicle to atmosphere, which may reduce a release of undesired evaporative emissions to atmosphere.

A method and a system for detection of torque deviations of an engine (101) in a vehicle (100). A measurement (201) is made of actual measured values D.sub.act related to a behavior of at least one parameter which is related to an actual torque M.sub.eng.sub._.sub.act delivered by the engine (101). This actual torque M.sub.eng.sub._.sub.act is delivered here by the engine (101) in consequence of a torque M.sub.eng.sub._.sub.req demanded from the engine (101). A comparison (202) is then made of the actual measured values D.sub.act which are related to the behavior of the at least one parameter with previously determined measured values D.sub.ref of correspondingly at least one respective parameter related to the actual torque M.sub.eng.sub._.sub.act. The previously determined measured values D.sub.ref will here have been determined during normal operation of the vehicle (100). Detection is then made of whether the actual measured actual torque M.sub.eng.sub._.sub.act deviates from the demanded torque M.sub.engj-eq. The detection is based here on the comparison of the actual measured values D.sub.act with the previously determined measured values D.sub.ref.

An engine control device controls an engine including a turbo-supercharger, a waste gate valve, an air-bypass valve, and a high-pressure fuel system. The engine control device includes: an air-bypass valve control unit and an abnormality detection unit. The air-bypass valve control unit controls the air-bypass valve. The abnormality detection unit detects an abnormality in the high-pressure fuel system. The air-bypass valve control unit increases an opening degree of the air-bypass valve in accordance with detection of the abnormality by the abnormality detection unit.

A method for introducing a gaseous fuel into a combustion chamber of an internal combustion engine includes forming a non-ignitable mixture of the gaseous fuel and a gas including oxygen in a predefined mixture mass ratio within a predetermined range of tolerance having a pressure suitable for directly introducing the non-ignitable mixture into the combustion chamber during at least the compression stroke; and introducing the non-ignitable mixture directly into the combustion chamber.

An engine control device sets a target value for the engine oil temperature appropriately in an engine that uses gasoline as a fuel, even when the fuel does not have a single boiling point because the gasoline is a mixed composition, or when the fuel property changes (for example, when the vaporization property changes due to deterioration). In other words, the engine control device prevents excessive heating or insufficient heating by changing the oil temperature to the high side in a condition wherein the fuel being used does not easily vaporize, and changing the oil temperature to the low side in a condition wherein the fuel being used easily vaporizes. This engine control device includes an oil temperature controller that controls the temperature of oil lubricating the interior of the engine; a fuel supply device that supplies fuel to the engine; and a detector for detecting the property of the fuel. The temperature of the oil is controlled on the basis of a signal from the detector.

A method for checking the operation of a high-pressure fuel supply unit for an internal combustion engine, consisting in driving a high-pressure fuel injection pump by a starter, and after the engine is synchronised and fuel injection into the cylinders is shut off, in defining an initial base pressure in a high-pressure rail, in activating the injection pump by issuing successive timing and angle-setting commands, on the basis of the initial pressure, and in comparing the first pressure and the second pressure obtained in the rail by these timing and angle-setting commands, and/or by comparing at least one of the pressures with a reference pressure in order to check the operation of the high-pressure fuel supply unit for the internal combustion engine

A method for controlling a plurality of injectors installed in the same cylinder of an engine may include determining whether an electrical failure occurred in any of the injectors, and entering a fail-safe mode when an electrical failure has occurred only in one of the plurality of injectors in the same cylinder. In the fail-safe mode, fuel supply to an injector that has experienced an electrical failure is cut off, and the amount of fuel injected into the cylinder by a normally operating injector is increased.

A method of evaluating operability of a gaseous fuel admission valve of an internal combustion engine is disclosed. The method includes operating the internal combustion engine on gaseous fuel by repeatedly actuating the gaseous fuel admission valve. The method further includes measuring a sequence of temporal developments of an electrical operation parameter respectively associated with an actuation of the gaseous fuel admission valve. The sequence includes a first temporal development to be evaluated and a plurality of temporal developments preceding the first temporal development. The method also includes evaluating operability of the gaseous fuel admission valve based on the first temporal development of the measured sequence and at least one of the plurality of preceding temporal developments of the measured sequence.

Internal combustion engine (1) with a controller (2) and at least one combustion chamber (3) and an at least one ignition amplifier (4) associated with the combustion chamber (3), whereby the at least one combustion chamber (3), on the one hand via a feeding device (5) for a fuel-air mixture, can be supplied with energy, and on the other hand can be supplied with energy by the associated ignition amplifier (4), whereby the controller (2) is designed to change the excess-air ratio () of the fuel-air mixture in a detection mode for the at least one combustion chamber (3), and at least one sensor (6) is provided, whose signals can be supplied to the controller (2) and whose signals are characteristic of the combustion event in at least one combustion chamber (3) and that the controller (2) is designed such that, depending on the signals supplied by at least one sensor (6), a representative detection signal is generated associated with a status of the at least one ignition amplifier (4) associated with at least one combustion chamber (3).