Gas prices continue to creep up as summer vacation time nears. And as consumers keep a  wary eye on those gas prices, consumer advocates and auto specialists are warning drivers away from myths that supposedly help them save money on gas.

Some of the myths that consumers are being warned about include:

1. Airflow gadgets

Consumer Reports tested several devices that claim to increase gas mileage by forcing more air through the engine.  These devices, such as the Fuel Genie ($89.95, plus shipping), were not found to have a measurable savings.  While many claim fuel savings of up to 50%, consumers won’t even recoup the cost of the equipment.

2. Fuel additives did a review of fuel treatments that claim to increase gas mileage.  They cite approval by the Environmental Protection Agency (EPA), suggesting the product claims have been verified.  However, the EPA testing only encompasses measuring harmful emissions.  Gas suppliers already place additives in their fuel to maximize efficiency and keep engines running clean.

3. Premium fuel

While using premium gas is a necessity in many premium automobiles, most vehicles are designed to operate on lower octane gas.  Most vehicle owner manuals specify the optimum octane; using an octane boost or filling up with premium fuel that surpasses the car’s octane rating can cause the engine to be less efficient.

According to the Federal Trade Commission, “in most cases, using a higher octane gasoline than your owner’s manual recommends offers absolutely no benefit. It won’t make your car perform better, go faster, get better mileage or run cleaner. Your best bet: listen to your owner’s manual.”

4. Over-inflated tires

The theory that has been spread is that over-inflated tires will reduce road friction, thereby easing the power needed to keep the car rolling.  However, this fails two address to key factors.  The road friction is also what allows cars to handle properly, and over-inflated tires wear out much quicker. tested the theory and found the fuel consumption variance to be negligible, recommending that drivers follow the specified tire pressure.

5. Avoid using air conditioning published a list of money-saving tips, including telling drivers to roll down their windows and turn off their air conditioner (AC).  It drew a backlash from readers extolling that increased drag negates the energy savings.

According to Consumer Reports and, this is only partly accurate.  Consumer Reports’ testing shows that using the AC reduces fuel economy by up to 10%.  Driving around town, at speeds under 35 MPH, the added drag on the vehicle is minimal.

“But as your speed increases to 45 MPH, or highway speeds,” says Jason Toews, co-founder of, “wind drag becomes an issue. Driving with the windows down increases the drag on your vehicle, resulting in decreased fuel economy by up to 10 percent. Drive at speeds over 55 mph with windows down and you’ll decrease fuel economy by up to 20 percent or greater.”