Photo by: by John Dixon

Rich Schrock, co-owner of TK Service Center, cleans fuel injectors in a car at his shop Friday in Urbana. Schrock says typical gas-saver products usually don't work.

In an age of $3 per gallon gas, how does this sound: Attach a device to your car, say a magnet on the fuel line, and voila.

Your gas mileage increases by 20 percent.

Or maybe the boost is promised by installing some tubes and a reservoir in your car, allowing microscopic platinum particles to help gas burn more efficiently.

Television and Internet pop-up ads for so-called gas-saver products may sound scientific and technical (i.e. "ionizers" and "moleculetors"), but the fact is there is no silver bullet when it comes to improving gas mileage.

"The bottom line is I don't have a lot of faith in them," said Mike Donovan, automotive program director at Parkland College.

"In general there's a lot of things that prove to be scams. There are not a lot of cheap, easy accessories to put on the car to get better gas mileage," added mechanic Rich Schrock with TK Service Center in Urbana.

The Environmental Protection Agency has tested more than 100 devices that claim to improve gas mileage and none significantly improves gas mileage. Some may even increase exhaust emissions, according to the Federal Trade Commission.

Consumer Reports magazine has tested many products over the years (such as the Platinum Gas Saver and the Fuel Genie) and found none significantly improved gas mileage.

Instead, the magazine has recommended drivers follow the car manufacturer's service schedule in order to maintain good gas mileage.

At a time when gas prices are high and advertising for such products may increase, the FTC advises consumers to be on the lookout for claims that a product improves fuel economy by 20 percent.

And be wary of claims the product is approved by the federal government. No government agency endorses or approves gas-saving products for cars, according to the FTC.

If the manufacturer claims the product has been evaluated by the EPA, you can request a copy of that report from the EPA's Web site, www.epa.gov.

If you bought the product and are not happy with the results, call the manufacturer and ask about a refund, recommends the FTC. If you're not happy with the company's response, contact the Illinois Attorney General's office or Better Business Bureau.

Finally, if you do want to get good gas mileage (and downsizing to a smaller car or buying a hybrid is not on your list), consider the following standard advice.

"Nine out of 10 certified, legitimate technicians will advise people instead to keep the engine tuned, the filters clean and slow down a little bit," Donovan said.

Some additives sold at car accessories stores may legitimately help the car run better, which in turn will keep you from losing gas mileage, Donovan said.

"They make oil a little slicker, which reduces friction and that's pretty well documented," he said. Donovan and Schrock recommended cleaning the fuel injectors.

Carbon can build up in the engine and restrict air and fuel flow into the engine.

If you notice a decrease in performance, if you're losing mileage and the car is running a little roughly, you may need the fuel injectors cleaned.

"The best thing to do is keep everything maintained properly," Schrock said.