Beware Gimmicks Promising Better Mileage

Ever-increasing gas prices are sending motorists in search of sometimes unconventional ways to improve their cars' gas mileage.

Some products are geared heavily toward consumers and promise to make nearly any vehicle more fuel efficient. But "Good Morning America" technology contributor Becky Worley discovered some items may not live up to their fuel-efficient claims, which use additives, reformulators and special magnets as gimmicks.

Check which items Worley found useful and which didn't make the grade.


At $45 per 32-ounce bottle, it claims to increase fuel efficiency between 7 and 19 percent.


What Becky Says

I have not seen any changes in fuel efficiency as a result of adding the liquid to my gas tank. To further my belief that this is a dubious product, when I called some of the distributors listed online for Ethos, the first two numbers were cell phones that were no longer in service and the third had a message saying the person was "locked up" until July 7.

What the Experts Say

The Environmental Protection Agency has evaluated or tested more than 100 alleged gas-saving devices and has not found any product that significantly improves gas mileage. In fact, some so-called gas-saving products may damage a car's engine or cause a substantial increase in exhaust emissions.

Gas-Saving Magnets

The fuel saver's magnet claims it has been tested and approved by an EPA-accepted laboratory to increase fuel economy up to 11.6 percent.

It gives a seemingly scientific online explanation for why the product works, including claims that clustered fuel molecules cause incomplete fuel burning.

What the Experts Say

The EPA has tested all kinds of fuel-line magnets, but no magnetic technology has ever been proven to improve mileage. The science is fundamentally flawed. Fuels in most engines burn at 99 percent efficiency. There's no leftover energy that escapes. Even if the magnets did break up fuel clusters, they'd only be able to improve fuel efficiency by 1 percent.

Plus, if this worked, why wouldn't car manufacturers have the technology built into their cars? The Federal Trade Commission has gone after marketers of fuel-line magnets in the past but the products just keep popping up.

Using Water to Improve Gas Mileage

The claim is that by using water hooked up to your car battery, you use electrolysis to create energy and double your fuel efficiency. To do this you attend a seminar for $145 or buy a converter for $185.

What the Experts Say

There is a lot of controversy online about this technology. On one hand, people believe that the law of conservation of energy says you can't make fuel out of nothing. Others say that it can improve engine efficiency. Basically, I don't think it's worth doing the experiment on your own car. I talked to AAA and officials there warn that this kind of modification could void your warranty and end up costing you in repairs in the long run. And if this was such a straightforward economizer, with hybrid sales up 25 percent, why aren't the major manufacturers putting a mason jar and some tubing in their engines to increase fuel efficiency?

Fuel Mizer

For $69 you can purchase a Fuel Mizer that mounts on your car's dashboard and lets you know when your driving patterns are decreasing fuel efficiency.

What Becky Says

I am using the Fuel Mizer now on my mini-van and it's great. There's no installation. You just stick it to the dash board where you can see it. It tells you when you are accelerating too fast or braking too hard, and curtailing these two activities as much as possible can help to improve your fuel efficiency.

It beeps at you and flashes lights to communicate your driving habits and that gets a little annoying. I probably won't drive with it on all the time but it's beneficial for retraining me. I'm more aware of my inefficient driving habits.

What the Experts Say

Car and Driver magazine tested the Fuel Mizer and reported a 10 percent increase in fuel economy.

One note: I used the fuel additive but I can't give you any kind of quantitative number for what mileage changes I experienced. From everything I've read, this kind of testing needs to be done in a very controlled environment and I would be a total hack if I tried to represent anything other than my qualitative experience with the products.

Gut Gas Guzzling Without Gadgets

Here are some tips to improve your vehicle's efficiency without using gadgets or additives.

Replace your air filter.

Make sure your tires are inflated properly.

Remove ski racks or cargo carriers from the vehicle.

Finally, use cruise control and drive less than 60 miles an hour to conserve fuel.