A fuel vapor treatment apparatus includes a controller configured to detect an abnormality in at least one of a first check valve, a second check valve, a second purge passage, a charging passage, and an ejector based on pressure detected by a pressure detector.

A fuel vapor treatment apparatus includes a controller configured to detect an abnormality in at least one of a first check valve, a second check valve, a second purge passage, a charging passage, and an ejector based on pressure detected by a pressure detector.

Methods and systems are provided for a diagnostic of a pressure sensor. In one example, a method includes bypassing one or more vapor canisters and determining a condition of the pressure sensor based on feedback from a hydrocarbon sensor.

A vaporized fuel treating device having a canister that is configured to adsorb vaporized fuel in a fuel tank and to feed the adsorbed vaporized fuel to an engine may include a pressure sensor that is configured to periodically detect an inner pressure of the fuel tank, and a pressure sensor failure determination device that is configured to determine that the pressure sensor has failed when a change of the inner pressure detected by the pressure sensor in a unit of time is not less than a predetermined pressure value that is greater than a maximum value of possible pressure changes within the fuel tank.

Embodiments for controlling fuel vapors are disclosed. In one example, a method comprises during a purge of a fuel vapor canister, adjusting a heater of the fuel vapor canister based on a rate of a purge flow exiting the fuel vapor canister and a concentration of hydrocarbons released from the fuel vapor canister. In this way, a fuel vapor canister purge efficiency may be increased.

Methods and systems are provided for opportunistically conducting an evaporative emissions test diagnostic procedure in order to indicate the presence or absence of undesired evaporative emissions in a vehicle evaporative emissions control system and fuel system. In one example, tire pressure and barometric pressure are monitored, and responsive to a tire pressure decrease in the absence of a barometric pressure increase, along with an indication that the vehicle transmission is in neutral and that the vehicle is not traveling downhill, the evaporative emissions system and fuel system may be sealed and the presence or absence of undesired evaporative emissions indicated based on a vacuum-build. In this way, an opportunistic evaporative emissions test may be conducted based on conditions favorable to conducting an emissions test procedure, and may thus increase test completion rates and reduce undesired evaporative emissions.

A purge device includes a canister; a purge passage configured to extend from the canister and be connected to an upstream side of a compressor of a supercharger in an intake passage; a supply unit configured to supply purge gas to the upstream side of the compressor in the intake passage during supercharging; a throttle configured to be provided in a portion of the intake passage connected with the purge passage and limit an inflow of gas from the purge passage; a sensor configured to detect internal pressure downstream of the supply unit in the purge passage; and a control device configured to determine that a passage end of the purge passage deviates from the intake passage, in a case where a detection value obtained by the sensor during the operation of the supply unit is lower than a predetermined pressure.

A diagnosis apparatus of a fuel supply system includes an operation state detector, an air-fuel ratio sensor, a fuel injection amount calculator, a threshold value table, an abnormality information acquiring device, and an abnormality determining device. In the threshold value table, operation ranges of an internal combustion engine are provided based on an engine speed and a throttle opening. In the threshold value table, a lean side threshold value and a rich side threshold value of an air-fuel ratio correction factor to determine abnormality of the fuel supply system are set beforehand for each of the operation ranges. The abnormality information acquiring device is configured to determine whether the air-fuel ratio correction factor has exceeded the lean side threshold value or the rich side threshold value extracted from the threshold value table according to an operation state so as to acquire abnormality information.

A vehicle, a vehicle fuel reactant leak detection system, a computer program product, and a computer implemented method of detecting leakage of a fuel reactant from a vehicle. The vehicle includes one or more fuel cell modules, a fuel supply source to supply a fuel reactant to the one or more fuel cell modules via a high-pressure fuel supply line, a fuel supply valve configured to open and close fuel reactant flow through the high-pressure fuel supply line, and a computing device, operatively connected to the fuel supply source. The computing device includes one or more processors caused to conduct, in response to a detection as sensor data of pressure in the high-pressure fuel supply line when the vehicle engine is in a non-operating state, fuel pressure analysis of the sensor data, and detect, based on the fuel pressure analysis, leakage of the fuel reactant at the fuel supply valve.

A method is provided for operating an internal combustion engine, which comprises at least one combustion unit, a fresh gas tract for supplying fresh gas to the combustion unit, and a fuel tank system. A fresh gas compressor as well as a differential pressure valve are integrated into the fresh gas tract. The first purge gas line opens into a first section of the fresh gas tract, which is situated downstream from the differential pressure valve as well as upstream from the fresh gas compressor, while the second purge gas line opens into a second section of the fresh gas tract situated downstream from the fresh gas compressor. The differential pressure valve is at least partially closed at least temporarily during an intake mode of the internal combustion engine with fuel vapor filter purging, and purge gas is introduced into the fresh gas tract via the first purge gas line.