Patent ID: 7032630

Claim:
A fueling system for a vehicle comprising: a fuel storage tank for containing liquid fuel and an ullage space; a fuel pump for pumping the liquid fuel from the storage tank to a fuel tank of the vehicle; a nozzle assembly coupled to a hose for delivering the fuel being pumped from the storage tank to the fuel tank; a vapor pump coupled to the hose and in communication with the nozzle for extracting vapor displaced from the fuel tank and delivering the vapor to the ullage space of the fuel storage tank; a vapor flow meter in communication with the vapor pump for measuring a flow rate of the vapor; a fuel flow meter in communication with the fuel pump for measuring a flow rate of the fuel; a diagnostic agent in communication with the vapor flow meter and the fuel flow meter to generate a ratio of the flow rate of the vapor to the flow rate of the fuel; and a control interface in communication with the diagnostic agent and at least one of the fuel pump and the vapor pump to provide a feedback signal to the at least one pump to adjust the flow through the at least one pump based on the ratio of the vapor and fuel flow rates.