Flexible Fuel VehiclesFlexible fuel vehicles (FFVs) have an internal combustion engine and are capable of operating on gasoline and any blend of gasoline and ethanol up to 83%. A flexible-fuel vehicle (FFV) or dual-fuel vehicle is an alternative fuel vehicle with an internal. What is the definition of FFV? What is the meaning of FFV? How do you use FFV in a sentence? What are synonyms for FFV?. Looking for the definition of FFV? Find out what is the full meaning of FFV on Abbreviations. A flexible-fuel vehicle (FFV) is a vehicle with an internal combustion engine capable of operating on a mixture of fuels, typically gasoline and ethanol.