A method for monitoring for a rupture in a storage element of a fuel tank system having a fuel tank includes: detecting, by a mass flow sensor, thermal conductivity of an unmoved air mass in a first line of the fuel tank system; and identifying a rupture in the storage element if the detecting by the mass flow sensor detects a change in the thermal conductivity of the unmoved air mass in the first line when a second valve is in a closed state and/or when an air pump is at a standstill.

A method for localizing restrictions in a fuel system during refueling, comprising: monitoring fuel tank pressure, fuel vapor canister temperature, and evaporative leak check module pressure during a refueling event; and responsive to a premature shutoff event, indicating a location of a restriction among a plurality of locations based on whether monitored pressure and temperature changes during the refueling event are greater than respective thresholds. In this way, the cause of a premature shutoff event may be diagnosed without requiring additional sensors within the fuel system.

A system according to the present disclosure includes a valve control module, a purge fraction module, and a diagnostic module. The valve control module opens a purge valve in an evaporative emissions system to allow purge vapor to flow to an intake system of an engine. The purge fraction module determines first and second fractions of purge vapor delivered to the engine relative to a total amount of air and purge vapor delivered to the engine based on first and second inputs, respectively. The first input is from a hydrocarbon sensor disposed in the evaporative emissions system of the engine. The second input is from an oxygen sensor disposed in an exhaust system of the engine. The diagnostic module selectively diagnoses a fault in at least one of the evaporative emissions system and the hydrocarbon sensor based on the first and second purge fractions when the purge valve is open.

Systems and methods for diagnosing individual components of an evaporative emissions system are presented. In one example, fuel vapor flow may be a basis for determining whether or not selected emission system components may be degraded. Further, fuel tank pressure may be another basis for determining component whether or not selected emissions system components may be degraded.

A compressor arrangement for an internal combustion engine, having a compressor which is arranged in a compressor housing and has a low pressure side and a high pressure side, and having a negative pressure provision unit, which has a propellant channel that is fluidically connected, on the one hand, via a propellant inlet fitting to the high pressure side of the compressor and, on the other hand, via a propellant outlet fitting to the low pressure side of the compressor and has a nozzle, and which has a negative pressure channel opening into the propellant channel fluidically between the propellant inlet fitting and the propellant outlet fitting.

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.

An evaporated fuel processing device utilizing a flow rate control valve as a valve positioned in a passage connecting a fuel tank with a canister. The device includes: a valve opening means for opening the flow rate control valve at a constant speed; an internal pressure sensor; a valve opening start position detecting means for acquiring a second derivative value of the internal pressure after a valve opening motion of the flow rate control valve has started and for detecting a valve opening start position of the flow rate control valve based on the second derivative value; a learning means for storing the valve opening start position; and a valve opening speed change means for changing a valve opening speed of the valve opening means based on a variation speed of the internal pressure before the valve opening motion of the flow rate control valve has started.

An engine control device configured to control an engine includes: a turbocharger having a turbine that is configured to be driven by exhaust gas of the engine; and a compressor coupled to the turbine and configured to compress fresh air; an air-bypass passage that communicates between an upstream and a downstream of the compressor; an air-bypass valve configured to open/close the passage; a canister configured to store evaporated fuel gas generated in a fuel tank; an ejector configured to suction the evaporated fuel gas from the canister by using differential pressure between the upstream and the downstream of the compressor and introduce the evaporated fuel gas to the upstream; a purge valve configured to open/close a purge passage through which the evaporated fuel gas is to delivered from the canister to the ejector; and a purge valve diagnosis unit configured to detect stuck open malfunction of the purge valve.

A method is provided, comprising indicating a fuel vapor canister load based on a steady-state pressure 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.

Methods and systems are provided for conducting an evaporative emissions test responsive to an indication of a vehicle remote engine start event. In one example, responsive to an indication of a remote start and further indication that the vehicle is not occupied, intake manifold vacuum is utilized to reduce pressure in the fuel system and evaporative emissions system to a threshold, wherein the fuel system and evaporative emissions system are sealed, and undesired evaporative emissions indicated responsive to a pressure bleed-up rate greater than a threshold. In this way, by applying intake manifold vacuum on the fuel system and evaporative emissions system while the vehicle is stationary and not occupied, engine hesitations resulting from desorption of fuel vapors from a fuel vapor canister are not experienced by the vehicle operator and/or passengers, and noise factors from driving conditions, passenger movement, etc., do not impact the evaporative emissions test.