The Mercedes Viano is essentially a van with more seats, so there's loads of interior space..rash tested in 2008 by Euro NCAP the Viano scored four stars for adult safety and three for children. The mechanical build quality of the Viano is very high as it shares a platform with Mercedes' highly dependable commercial van, the Vito.
Expert hypermiler Wayne Gerdes set a new Guinness World Record for fuel economy in a 2013 Volkswagen Passat TDI, a diesel-powered midsize sedan. The Passat used just 104.94 gallons of fuel for an average fuel economy of 77.99 miles per gallon. That beats the old record, established in 2009 by an Australian couple. Over their 9,505-mile trip, Helen and John Taylor averaged 67.90 miles per gallon in a 2009 Volkswagen Jetta TDI.
Most cars has 10 to 18 gallon (37.8 to 68.04 liter) fuel tanks 30 miles per gallon means you can drive 30 miles (48.27 KM) using only 1 gallon (3.78 L) of fuel The 1.4L your talking about sounds like your engine size.That means your engine has a displacement of 1.4L..imply put, miles per gallon refers to how many miles you can drive on a single gallon of gas. So, if your car does 30 mpg, that means that you can drive 30 miles on a gallon of gas.