Fuel Overflows While Refueling

Check EVAP system. See DTC P0451, P1456 or P1457 in 2000-01 SELF-DIAGNOSTICS -- NSX & NSX-T article and 2000-01 SYSTEM & COMPONENT TESTING -- NSX & NSX-T article.
Check onboard refueling vapor recovery vent shut valve. See 2000-01 SYSTEM & COMPONENT TESTING -- NSX & NSX-T article.