Gas prices are up, and so is volume of advertising for "gas-saving" products. When gasoline prices rise, consumers often look for ways to improve fuel efficiency. Although there are practical steps you can take to increase gas mileage, Federal Trade Commission (FTC) warns you to be wary of any gas-saving claims for automotive devices or oil and gas additives. Even for few gas-saving products that have been found to work, savings have been small.

"Gas-Saving" Advertising Claims

Be skeptical of following kinds of advertising claims.

"This gas-saving product improves fuel economy by 20 percent."

Claims usually tout savings ranging from 12 to 25 percent. However, Environmental Protection Agency (EPA) 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 "gas-saving" products may damage a car's engine or cause substantial increases in exhaust emissions.

The gas-saving products on market fall into clearly defined categories. Although EPA has not tested or evaluated every product, it has tried to examine at least one product in each category. See "Devices Tested by EPA" at end of this brochure for category descriptions and product names.

"After installing your product on my car, I got an extra 4 miles [6.4 kilometers] per gallon [3.8 liters]."

Many ads feature glowing testimonials by satisfied customers. Yet, few consumers have ability or equipment to test for precise changes in gas mileage after installing a gas-saving product. Many variables affect fuel consumption, including traffic, road and weather conditions, and car's condition.

For example, one consumer sent a letter to a company praising its "gas-saving" product. At time product was installed, however, consumer also had received a complete engine tune-up - a fact not mentioned in letter. The entire increase in gas mileage attributed to "gas-saving" product may well have been result of tune-up alone. But from ad, other consumers could not have known that.

"This gas-saving device is approved by Federal government."

No government agency endorses gas-saving products for cars. The most that can be claimed in advertising is that EPA has reached certain conclusions about possible gas savings by testing product or by evaluating manufacturer's own test data. If seller claims that its product has been evaluated by EPA, ask for a copy of EPA report, or check www.epa.gov for information. In some instances, false claims of EPA testing or approval have been made.

Product Complaints and Refunds

If you're dissatisfied with a gas-saving product, contact manufacturer and ask for a refund. Most companies offer money-back guarantees. Contact company, even if guarantee period has expired.

If you're not satisfied with company's response, contact your local or state consumer protection agency or Better Business Bureau.

EPA Evaluation Efforts

The EPA evaluates or tests products to determine whether their use will result in any significant improvement or detriment to fuel economy. However, EPA cannot say what effect gas-saving products will have on a vehicle over time because it hasn't conducted any durability tests. It's possible that some products may harm car or may otherwise adversely affect its performance. In fact, today's vehicles' emission control systems are very sophisticated and complex. They have On Board Diagnostic features that alert driver to problems associated with emission control and fuel delivery systems. Retrofit products may have an adverse effect on these systems.

Devices Tested by EPA

The following list categorizes various types of "gas-saving" products, explains how they're used and gives product names. Those with asterisks may save measurable, but small, amounts of gas. All others have been found not to increase fuel economy.

Air Bleed Devices: These devices bleed air into carburetor. They usually are installed in Positive Crankcase Ventilation line or as a replacement for idle-mixture screws.