The Ultimate Fuel-saving Device Hoax Quiz

By: Staff

4 Min Quiz

Image: refer to hsw

About This Quiz

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?

A variety of devices claim that they use ionic charges or catalytic action to alter fuel into a more efficient form. An equal variety of reasons, from onboard engine computer adjustments to basic chemistry, make these claims dubious at best.


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

While running your air conditioner in stop-and-start driving conditions will burn slightly more gas than normal, the drag of driving at highway speeds with the windows down is less efficient than using the air conditioning when underway.


Where was water injection first used?

Water injection was developed during World War II to help fighter pilots prevent detonation in high-compression engines running on low-octane gas. The same technology can protect a high-performance car engine, but it does little for mileage.


How does hydrogen compare to gasoline?

While hydrogen carries more than 10 times the specific energy of gasoline, its low energy density means hydrogen is a much more difficult fuel to use for vehicles -- it's hard to store enough to provide adequate range.


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

While electrolysis is a simple process for producing hydrogen from water, the hydrogen produced from the process is often 25 percent of the amount of energy required to make it.


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

Petroleum fuels are too stable to be significantly altered by something as small and simple as a magnet placed on a fuel line. Even if a magnet could produce a significant electrical field, it would be altered by the metal of the fuel line, the tank and its components.


Do high-flow air filters improve fuel efficiency?

While a high-flow air filter does reduce restrictions on an engine's intake, possibly increasing horsepower, the engine will compensate by injecting more fuel into the engine, negating any big fuel-saving claims.


What does an intake vortex device actually do?

Intake vortex devices claim to improve fuel-air mix -- and efficiency -- by altering airflow into the engine. In reality, these often act as restrictor plates, limiting horsepower and wasting gas.


How does an engine react to a vapor injector?

A fuel vapor injector can cause a car's cylinders to run rich -- with too much fuel. The engine's computer will limit fuel flow, negating any advantage the injector claims to offer.


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

Gasoline in liquid form burns too slowly to be useful for combustion, but vaporized gasoline burns at the high rate necessary to power an internal combustion engine.


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