The present invention relates to a propane shutoff system. The system may include a regulator having a first section, and may further include a fuel lock-off in fluid communication with the regulator. The fuel lock-off is operable to stop a flow of fuel into the regulator. The system may also include a high pressure switch for monitoring pressure entering the regulator, and a low pressure switch for monitoring pressure within the first section of the regulator. The high pressure switch may cause the fuel lock-off to stop the flow of fuel into the regulator upon detection of a pressure entering the regulator higher than a predetermined value. The low pressure switch may cause the fuel lock-off to stop the flow of fuel into the regulator upon detection of a pressure within the regulator higher than a predetermined value.

A fuel filter pre-fill detection system includes a monitoring mechanism structured to monitor a fluid property of a fuel system indicative of priming of the fuel system. A control mechanism is coupled with and structured to received data from the monitoring mechanism, and outputs a signal responsive a time to prime the fuel system that is indicative of a filter pre-fill state.

An engine control system includes a fuel injector and a sensor that is configured to provide a signal indicative of a temperature. A controller is in communication with the sensor. The controller includes a fuel injector driver in communication with the fuel injector. The fuel injector driver includes a saturated mode and a peak and hold mode. The controller is configured to command the fuel injector driver to control the fuel injector with one of the saturated mode or the peak and hold mode based upon the signal. For a high resistance injector, the peak and hold mode is used in cold weather conditions to break free an injector seal, and then the fuel injector driver reverts to the saturated mode.

Disclosed is a device for detecting any fixed closure of a fuel shut-off valve 7 which opens/closes a feed line 5 for feed of fuel 3 to a fuel addition valve 6. The device is provided with a pressure sensor 8 which detects a pressure of the fuel 3 between the fuel addition and shut-off valves 6 and 7 and a controller 9 which determines the fuel shut-off valve 7 to be fixed closed when a detection value of the pressure sensor 8 falls below a threshold set depending on a rotation frequency of an engine.

A fuel injection device including an injector that injects fuel into a cylinder of an engine; a fuel injection amount obtaining unit that obtains a fuel injection amount of fuel injected by the injector; a heat generation amount obtaining unit that obtains a heat generation amount of the fuel injected by the injector and ignited; and a control unit that determines that injector abnormality occurs, when determining that a difference between a fuel injection amount obtained by the fuel injection amount obtaining unit and a reference fuel injection amount is within a predetermined range and that a heat generation amount obtained by the heat generation amount obtaining unit is greater than a reference heat generation amount corresponding to the reference fuel injection amount. Accordingly, whether or not injection hole corrosion occurs in the injector can be determined.

A control device for a compression-ignited internal combustion engine includes a nozzle that includes plural injection holes arranged at intervals in the circumferential direction and that directly injects fuel to a combustion chamber, a piston that includes a cavity with an inner circumferential side surface to which a distance from the nozzle varies in the circumferential direction, a first injection hole for injecting fuel to a portion of the inner circumferential side surface to which the distance from the nozzle is the largest out of the plural injection holes, a second injection hole for injecting fuel to a portion of the inner circumferential side surface to which the distance from the nozzle is the smallest out of the plural injection holes, a detection unit that detects a heat release rate in the combustion chamber, and a control unit that determines which of the first and second injection holes is abnormal.

A diagnostic system for an engine includes: a plurality of cylinders, in-cylinder injectors, port injectors and an electronic control unit. The electronic control unit configured to make an abnormality diagnosis of an air-fuel ratio due to the in-cylinder injectors and then to make an abnormality diagnosis of the air-fuel ratio due to the port injectors. The electronic control unit is configured to make an abnormality diagnosis of the air-fuel ratio due to the in-cylinder injectors in an operating situation in which fuel is injected from only the in-cylinder injectors, and to make an abnormality diagnosis of the air-fuel ratio due to the port injectors by increasing a ratio of an injection amount of the port injectors when the electronic control unit has diagnosed that there is an abnormality of the air-fuel ratio in an operating situation in which fuel is injected from both the in-cylinder injectors and the port injectors.

Methods and systems are provided for restarting an engine when a high pressure fuel pump is degraded. In response to an indication of high pressure fuel pump degradation, fuel may be injected during an intake stroke, rather than a compression stroke, for a selected number of combustion events since the engine restart. By shifting to an intake stroke injection, the engine may be started even when sufficient fuel rail pressures are not available.

In the method provided herein, quantities of fuel are determined during a direct injection of a motor vehicle. In this connection, within one work cycle, test injections are carried out in two cylinders of an internal combustion engine of the motor vehicle during overrun phases, speed oscillations of moved masses of the cylinders are measured and a relative difference in quantity of the fuel quantity of the test injections within one work cycle is determined from the speed oscillations. By evaluating a relative signal between the test injections within one work cycle in the two cylinders, an intrinsic dependence of the drive train of the quantity of fuel signal is compensated.

A low pressure fuel pump control system of a GDI engine may include a low pressure fuel pump primarily pressurizing fuel supplied from a fuel tank, a high pressure fuel pump secondarily pressurizing fuel from the low pressure fuel pump, a low pressure fuel pump pressure sensor and a high pressure fuel pump pressure sensor detecting fuel pressure of the low pressure fuel pump and the high pressure fuel pump, and a fuel supply pressure controller setting a final target pressure of the low pressure fuel pump by correcting a reference pressure, wherein the reference pressure is corrected by a low pressure correcting pressure according to temperature of the low pressure fuel pump and a correction pressure.