John and Helen Taylor said they used their fuel-saving techniques, which they teach to students at their schools, to make the nine-day trek on only one tank of diesel in the six-speed manual car, USA Today reported Thursday.
The Passat has a government rating of 31 mpg in the city, 43 on the highway and 35 in combined city/highway driving.
The Taylors said their fuel economy-saving tricks include staying about 5 mph below all posted speed limits and never falling below a minimum posted speed limit on the highway. They said they also tried their hardest to avoid idling and having to turn the ignition off and on again.
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