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The Ultimate Fuel-saving Device Hoax Quiz
by Staff
Every driver would like to save a few dollars on gas. Consequently, the market for fuel-saving devices -- and fuel-saving hoaxes -- is large. See how well you can separate fact from fiction with our quiz on fuel-saving device hoaxes!

What do fuel ionizers and fuel catalysts claim to do?

  • minimize fuel flow using ionic fields
  • dissolve smog-producing agents in fuel
  • alter fuel to make it burn more efficiently

Is it more efficient to roll down the windows or use the air conditioner?

  • roll down the windows
  • use the air conditioner
  • use the air conditioner when at speed, but roll down the windows in start-and-stop traffic

Where was water injection first used?

  • in heavy locomotives in the 1940s
  • in propeller-driven fighters in World War I
  • in propeller-driven fighters in World War II

How does hydrogen compare to gasoline?

  • Hydrogen has higher specific energy and higher energy density than gasoline.
  • Hydrogen has lower specific energy and lower energy density than gasoline.
  • Hydrogen has higher specific energy but lower energy density than gasoline.

How efficient is electrolysis in a hydrogen generator in producing hydrogen?

  • about 25 to 40 percent efficient; not enough to produce fuel for transportation
  • efficient enough to replace 75 percent of a car's gasoline use
  • efficient enough to provide 30 percent of a car's gasoline use

True or false: Petroleum fuels can be significantly altered by fuel-line magnets.

  • true
  • false

Do high-flow air filters improve fuel efficiency?

  • no, although they could increase horsepower
  • yes, they increase efficiency by 20 percent
  • no, they reduce mileage and horsepower

What does an intake vortex device actually do?

  • It limits horsepower and acts as a restrictor.
  • It increases horsepower by smoothing out intake airflow.
  • It increases horsepower by making intake airflow more turbulent.

How does an engine react to a vapor injector?

  • It will burn fuel more efficiently, thanks to the added vapor.
  • It will compensate for the added vapor by limiting fuel flow.
  • It will increase fuel flow to make the vapor mixture richer.

True or false: Gasoline burns the same whether it's vaporized or in liquid form.

  • true
  • false