A method for a fuel system comprises receiving a first indication of inconsistency in a fuel level indicator output during a fuel consumption cycle, receiving a second indication of inconsistency in a fuel level indicator output during a refueling event, and indicating electrical degradation of the fuel level indicator responsive to the first and second indications of inconsistency indicating coincident ranges of inconsistency for the fuel level indicator output. By gauging the consistency of a fuel level indicator output during both upward and downward travel, electrical degradation may be distinguished from mechanical degradation. In this way, a range of inconsistency may be determined, and a reported fuel level adjusted while the fuel level indicator output is within the range of inconsistency.