John and Helen Taylor recently drove a 2012 Volkswagen Passat TDI carefully enough to return an unbelievable 84.1 mpg on trip from Houston, Texas, to Sterling, Va. That\'s 1,626.1 miles on one tank of low-sulfur diesel. That\'s almost 100 miles better than the old world record. The journey started on May 3 in Houston and lasted until May 5. The couple only traveled during the day and brought along 120 pounds of luggage. They also took turns driving and didn\'t travel more than 14 hours per day. The 2012 VW Passat TDI uses a 2.0-liter turbocharged diesel engine for power, delivering 140 hp and 236 lb-ft of torque. Volkswagen says it should be good for “just” 43 mpg on the highway. Exhaust gases are handled with VW\'s selective catalytic reduction system, which makes the car legal in all 50 states. The speedometer and odometer were calibrated before the drive by a state-certified testing station in Houston. Police officers oversaw the fill up and sealed the gas tank at the start of the trip. A Virginia sheriff\'s deputy verified the drive and unsealed the fuel tank. The Taylors conduct workshops on driving techniques and hold more than 90 fuel-economy records from around the world. It might not be the most exciting driving style, but there is something to be said for being able to spend your fuel budget on enjoying your vacation.