Method and system for fuel tank cap detection

Abstract

A method may verify that a fuel tank cap is present and properly closed after refueling of a motor vehicle fuel tank. The method may include, in response to a request for refueling: (a1) enabling refueling of the motor vehicle fuel tank by opening a first vent valve connected in series in a vent line, downstream from a first port of a recirculation line coupled to the vent line, so that to vent the motor vehicle fuel tank to the atmosphere through a fuel vapor canister; (b1) disabling refueling of the motor vehicle fuel tank by closing the first vent valve; (c1) monitoring the internal pressure within the motor vehicle fuel tank when the refueling request is finished; and (d1) concluding that the fuel tank cap is deemed present and properly closed when the internal pressure increases and/or remains higher than the atmospheric pressure.

Dependencies are inferred from the claim text.