The 2014 Volkswagen Jetta sedan has a fuel tank size of 14.5 gallons. This amount has been the same in the base sedan model since 1984.
According to the U.S. Department of Energy, the second generation of Volkswagen Jettas was introduced in 1984, and since then the base sedan model has come with a 14.5-gallon gas tank. The first generation, from 1979 to 1984, had a gas tank that held just over 10 gallons. The European models sometimes vary slightly in gas tank size. The Jetta SportWagens, which were introduced in 2009, have the same 14.5-gallon fuel tank capacity that the standard Jetta sedans do.