One embodiment of a fuel tank assembly includes a fuel sending unit having a float with a small thickness, which heretofore has been too thin to secure a stand-alone magnet thereon. The float may be manufactured in a complex shape or in a small size. In one embodiment the float may be manufactured of a material having magnetized particles interspersed throughout the float such that the float does not require a stand alone magnet secured thereon. The float may be manufactured of a material having a foaming agent added thereto so as to provide a finished product with air filled voids positioned throughout the float to increase the buoyancy of the finished float product.

Methods and systems are provided for diagnosing leaks/degradation in a fuel system. In one example, a system for a vehicle may comprise a variable volume device disposed within a fuel tank; an atmospheric port of the variable volume device fluidly coupled to a vent line upstream of a hydrocarbon sensor housed in the vent line, the vent line coupling a fuel vapor canister to atmosphere; and a controller storing instructions for monitoring output of the hydrocarbon sensor; and generating an indication of a degradation in the variable volume device based on the monitored hydrocarbon sensor. In this way, it is possible to effectively detect a degradation/leak in the variable volume device with minimal specialized components in the fuel system.

An ultrasonic element generates an ultrasonic wave and converts an input ultrasonic wave into an electric signal. A transmission circuit outputs a drive signal to the ultrasonic element. A comparator circuit outputs a first detection signal when the electric signal becomes larger than a threshold value and outputs a second detection signal when the electric signal becomes smaller than the threshold value. An arithmetic circuit computes a distance of a propagation path of the ultrasonic wave based on a time difference between an output timing, at which the ultrasonic element outputs of the ultrasonic wave, and a liquid level timing, at which the comparator circuit outputs the first detection signal, and based on a propagation speed of the ultrasonic wave. A storage unit stores a time difference between the first detection signal and the second detection signal. The transmission circuit increases the drive signal, as the time difference decreases.

A fuel system for a machine may include a fuel tank configured to hold cryogenic fuel, a pressure sensor, and an electronic control module (ECM). The ECM may determine a change in pressure of the fuel between a first time and a second time, determine a predicted change in pressure of the fuel between the first time and the second time, and determine that the change in pressure and the predicted change in pressure is greater than a threshold. Based on the change in pressure and the predicted change in pressure being greater than the threshold, a notification may be displayed associated with an integrity of the fuel tank.

A valve module for an operating fluid container system. The valve module has a housing which has a first connection for fluidically connecting to an operating fluid container interior, a second connection for fluidically connecting to a filler tube, and a third connection for at least indirectly fluidically connecting to the atmosphere. The valve module comprises the following features: the first connection is connected to the second connection and the third connection within the housing in a fluidic manner in each case; the second connection is connected to the third connection within the housing in a fluidic manner; and the first connection, the second connection, and the third connection can each be adjusted independently of one another between an open position, in which fluid communication through the respective connection is allowed, and a closed position, in which fluid communication through the respective connection is prevented.

The present invention relates to an all in one fuel tank assembly, and a process of manufacturing the same, for use in commercial vehicles, and more particularly, to an all in one fuel tank assembly that allows multiple components to be manufactured as a single integral structure, such as a single extruded device including a draw tube, a return tube, a fuel sender device, and a vent, for example.

Methods and systems are provided for diagnosing leaks in a fuel system. In one example, a method may include monitoring a fuel level in a vehicle fuel tank of the fuel system during refueling and indicating degradation of the vehicle fuel tank and/or a bellows coupled to the vehicle fuel tank based on the monitored fuel level. In some examples, indicating the degradation may further be based on a rate of fuel supplied to the vehicle fuel tank during the refueling and/or a vehicle fuel economy. In this way, degradation to the vehicle fuel tank and the bellows may be passively determined with minimal specialized components in the fuel system.

Methods and systems are provided for improving fuel economy and reducing undesired emissions. In one example, a method may include in response to an engine speed being within a first threshold speed of an engine idle speed during a speed reduction request with engine cylinders unfueled, maintaining the cylinders unfueled, and controlling the engine to a desired stopping position responsive to the engine speed being greater than a second threshold speed lower than the idle speed. In this way, fuel usage and emissions may be reduced and engine restart requests may be conducted at least in part via vehicle inertia.

A fuel measurement system and a fuel gauge error reduction method are provided. The fuel gauge error reduction method includes determining a driving mode of a vehicle based on an external input condition; calculating a remaining amount of fuel using a different manner corresponding to each driving mode; and providing the calculated remaining amount of fuel.

Vehicle fuel volume estimation systems and methods are provided herein. An example method includes determining a fuel level percentage value for a vehicle, determining a vehicle identification number (VIN) of the vehicle, determining a fuel tank part number using the VIN, converting the fuel level percentage value into a fuel volume value based on the fuel tank part number, and transmitting a message to a recipient, the message that includes the fuel volume value.