Abstract: A method for monitoring vapor-to-liquid flow rate in a fuel dispensing system with a vacuum assisted vapor recovery system having a coaxial hose with an outer fuel conduit for delivery of fuel and an inner vapor conduit for recovery of vapor includes the steps of: determining vapor flow rate in the inner vapor conduit; issuing a signal indicative of the vapor flow rate; determining liquid fuel flow rate in the outer fuel conduit; issuing a signal indicative of the liquid fuel flow rate; comparing the signal indicative of the vapor flow rate and the signal indicative of the liquid fuel flow rate; and, when vapor-to-liquid flow rate is outside a predetermined range, issuing a signal. A vacuum assist vapor recovery system, and a fuel dispensing system equipped with such a vapor recovery system are also described.