Patent attributes
Methods and systems are provided for preventing fuel tank overfilling during refueling events, wherein overfilling of the fuel tank is prevented by delivering a pressure pulse to the fuel tank responsive to a fuel fill level reaching a predetermined threshold, or responsive to an attempt to add additional fuel subsequent to the fuel fill threshold being reached. In one example, an onboard pressure vessel is actively pressurized via an onboard pump, where the pressure may be actively released and routed to the fuel tank to induce an automatic shutoff of a refueling dispenser pump under predetermined conditions. In this way, automatic shutoffs of refueling dispenser pumps may be rapidly and reliably induced, thus preventing fuel tank overfilling, prolonging the lifetime of fuel vapor storage canisters, and reducing undesired evaporative emissions.