A double-sided adhesive tape at a vehicle front-side is provided straddling from a first flange section to a second flange section so as to cover a vehicle width direction outer side end portion of a double-face contact portion. A determination circuit determines whether the present signals of a first signal line and a second signal line are the same or not. A measured spectroscopic absorbance or transmittance signal provides information for determining the concentration of the denaturant composition in the fuel ethanol. The centrifugal pump provides a desired fuel pressure for the fuel system.