A method is provided, comprising indicating a fuel vapor canister load based on a steady-state fuel vapor circulation rate in a vapor recovery line during a refueling event; and adjusting a canister purging operation in response to the indicated fuel vapor canister load. Restrictions in the vapor recovery line may increase the rate of fuel vapor canister loading during a refueling event. In this way, an accurate canister load may be determined following a refueling event, and canister purging operations adjusted accordingly.

A control apparatus includes an electronic control unit configured to: carry out a first diagnosis and a second diagnosis; control a first injection valve and a second injection valve such that fuel is injected from both the first injection valve and the second injection valve, and such that a fuel injection amount from the second injection valve is not reduced and a fuel injection amount from the first injection valve is reduced, when carrying out the first diagnosis; and control the first injection valve such that fuel is not injected from the first injection valve, and control the second injection valve such that the fuel injection amount from the second injection valve is reduced in a state where fuel is injected from the second injection valve, when carrying out the second diagnosis.

A system according to the principles of the present disclosure includes a fault command module, a fuel control module, and a fault detection module. The fault command module selectively generates a command to induce a fuel system fault based on a user input. The fuel control module automatically adjusts a fuel correction factor to a target value outside of a first predetermined range in response to the command to induce a fuel system fault. The fuel control module actuates a fuel injector associated with a cylinder of an engine based on the fuel correction factor. The fault detection module detects a fuel system fault when the fuel correction factor is outside of the first predetermined range.

The invention relates to a method for detecting the failure of injectors in an internal combustion engine, comprising the following steps: measuring a crank angle signal; transforming the crank angle signal into the frequency range by means of a discrete Fourier transformation; switching off each injector once and in a sequential manner; detecting and storing an angle of the harmonic of the 0.5th order of the Fourier-transformed crank angle signal for each switched-off injector once and in a sequential manner; continuous detection and storage of an angle and an amount of the harmonic of the 0.5th order of the Fourier-transformed crank angle signal; continuous comparison of the continuously detected amount with a predetermined threshold value, and determining a failure of the injector when the amount exceeds the predetermined threshold value; comparing the continuously detected angle with the angles stored for each switched-off injector when a failure of the injector is detected, and identifying the failed injector with an injector, for which a matching, stored angle is found.

A fuel vapor purge system includes: a fuel tank; a canister; a passage component that defines an intake passage of an internal-combustion engine; a purge pump pumping vapor fuel; and a valve device having a valve object, a main part having an internal passage, an inflow port through which the vapor fuel pumped from the canister flows into the main part, an outflow port connected with the inflow port through the internal passage and being opened to the intake passage, and a leak port connected with the inflow port through the internal passage and being opened to outside of the main part. The leak port has a leak preventive structure which prevents the vapor fuel from leaking to outside when the valve device is attached to the passage component such that the vapor fuel is able to flow into the intake passage.

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.

An evaporated fuel treatment device includes a canister, an evaporated fuel outflow detecting means, a pressure sensor, a pressure change detecting means, and a pressure sensor failure determining means. The canister adsorbs evaporated fuel from a fuel tank, and purges the adsorbed fuel to an engine. The evaporated fuel outflow detecting means undergoes a change in a signal as the evaporated fuel flows out of the fuel tank. The pressure sensor detects an inner pressure of the fuel tank. The pressure change detecting means detects whether or not the pressure is in a static state. When the evaporated fuel outflow detecting means detects that evaporated fuel has flowed out of the fuel tank and when the pressure change detecting means detects that the pressure is in a static state, the pressure sensor failure determining means determines that the pressure sensor is out of order.

A system according to the principles of the present disclosure includes a fault command module, a fuel control module, and a fault detection module. The fault command module selectively generates a command to induce a fuel system fault based on a user input. The fuel control module automatically adjusts a fuel correction factor to a target value outside of a first predetermined range in response to the command to induce a fuel system fault. The fuel control module actuates a fuel injector associated with a cylinder of an engine based on the fuel correction factor. The fault detection module detects a fuel system fault when the fuel correction factor is outside of the first predetermined range.

This invention refers to a method for diagnosing faults in the operation of a fuel heating system associated with an internal combustion engine, that includes a plurality of routines to detection of several kinds of faults. The relevant concern is to provide a sufficiently robust solution implemented by computer, to conceive a fuel heating system that includes a main control unit and a heating control unit independent from each other, both comprising respective intelligences so that this latter is particularly able to perform several functions and/or routines relating to the self-diagnostic of the heating system. For such, a method for self-diagnostic of fuel heating system that includes at least one engine control unit ECU that includes a respective microcontroller, and at least one heating control unit HCU that includes a respective microcontroller, both fed by at least one tension source 10 interconnected to each other and to the at least heating element 13 through an electronic circuit that still includes, at least, one main relay 11 and at least one secondary relay 12.

A system and method for detecting pressure deviation of a first fluid in an engine is disclosed. The method may comprise calculating, for each of a plurality of measurements, a delta between an actual first fluid pressure and a target pressure, summing each delta obtained from the calculating, and determining pressure deviation of the first fluid based on a cumulative sum of the deltas. In an embodiment, the first fluid may be natural gas.