A method for operating an internal combustion engine. The method includes: operating the internal combustion engine including a lambda regulation, which sets a fuel quantity to be supplied in accordance with a predefined setpoint lambda value, at preset times, carrying out a filter cleaning operation for a fuel tank ventilation, as a function of the presence of a release condition of the internal combustion engine, carrying out an adaptation of the lambda regulation by adapting at least one adaptation parameter as a function of operating variables of the internal combustion engine, at active filter cleaning operation and upon the presence of the release condition, operating variables which are required to carry out the adaptation of the lambda regulation being recorded, at deactivated filter cleaning operation and presence of the release condition, the adaptation of the lambda regulation being carried out as a function of the recorded operating variables.

A method for operating an internal combustion engine. The method includes: operating the internal combustion engine including a lambda regulation, which sets a fuel quantity to be supplied in accordance with a predefined setpoint lambda value, at preset times, carrying out a filter cleaning operation for a fuel tank ventilation, as a function of the presence of a release condition of the internal combustion engine, carrying out an adaptation of the lambda regulation by adapting at least one adaptation parameter as a function of operating variables of the internal combustion engine, at active filter cleaning operation and upon the presence of the release condition, operating variables which are required to carry out the adaptation of the lambda regulation being recorded, at deactivated filter cleaning operation and presence of the release condition, the adaptation of the lambda regulation being carried out as a function of the recorded operating variables.

The invention relates to a leak detection system on board of a vehicle comprising a fuel tank (301, 401), a filler pipe (302, 402), a venting line (303, 403) for recirculating fuel vapors from the tank to the filler pipe, said system having a combination pressure and temperature sensor mounted in the vapor dome of the fuel tank, and a pressure sensor located in the recirculation line above the highest possible liquid level that could be present in the recirculation line and to methods to detect said leak.

A diesel fuel and DEF combination tank provides a supplemental storage of diesel fuel and DEF for a vehicle. In particular, the combination tank comprises a first compartment for diesel fuel and a second compartment for DEF. Each compartment is provided with a respective outlet port for dispensing the fuel from the combination tank. Dispensing of fluid to the vehicle's fuel system is conducted by gravity feed or alternatively by pumping.

A diesel fuel and DEF combination tank provides a supplemental storage of diesel fuel and DEF for a vehicle. In particular, the combination tank comprises a first compartment for diesel fuel and a second compartment for DEF. Each compartment is provided with a respective outlet port for dispensing the fuel from the combination tank. Dispensing of fluid to the vehicle's fuel system is conducted by gravity feed or alternatively by pumping.

Methods and systems are provided for a fuel system. In one example, a method includes flowing fuel tank vapors to a catalyst during a fuel tank depressurization in response to a refueling request. The method further includes executing an engine vapor flush following a refueling event being completed.

A fuel tank includes a built-in component having a head portion, a neck portion, and a shoulder portion, the built-in component being anchored to a tank body by blowing air from outside a parison to cause the parison wrap around the neck portion during molding of the tank body. A slit extending in one direction only is formed on a surface of the shoulder portion as an air vent path.

A fuel tank includes a built-in component having a head portion, a neck portion, and a shoulder portion, the built-in component being anchored to a tank body by blowing air from outside a parison to cause the parison wrap around the neck portion during molding of the tank body. A slit extending in one direction only is formed on a surface of the shoulder portion as an air vent path.

There is provided a valve device including: a housing; a float valve; and a pressure adjusting valve. A first valve seat is formed from a peripheral edge of a valve hole. An accommodation portion is provided in a protruding manner from a surface of a partition wall. An inner periphery of the accommodation portion is provided with a reduced diameter portion and an increased diameter portion. A height of an upper end of the reduced diameter portion is equal to or greater than a front surface of the pressure adjusting valve in a state where the pressure adjusting valve is in contact with the first valve seat. The pressure adjusting valve is configured to be beyond the upper end of the reduced diameter portion when the pressure adjusting valve is raised to a maximum due to an increase in pressure in a fuel tank.

There is provided a valve device including: a housing; a float valve; and a pressure adjusting valve. A first valve seat is formed from a peripheral edge of a valve hole. An accommodation portion is provided in a protruding manner from a surface of a partition wall. An inner periphery of the accommodation portion is provided with a reduced diameter portion and an increased diameter portion. A height of an upper end of the reduced diameter portion is equal to or greater than a front surface of the pressure adjusting valve in a state where the pressure adjusting valve is in contact with the first valve seat. The pressure adjusting valve is configured to be beyond the upper end of the reduced diameter portion when the pressure adjusting valve is raised to a maximum due to an increase in pressure in a fuel tank.