ATLANTA -- A CBS 46 News investigation found that you may be paying for gas you aren’t getting.

CBS 46 News has learned that in the state of Georgia there are more than a 140,000 gas pumps, but only two dozen pump inspectors. The Commissioner of the Department of Agriculture, who is charged with overseeing the state’s gas pumps, said that they try to inspect every pump at least once every 18 months. But we found inspection stickers on pumps dating back to 2005. Some pumps even had a blank sticker.

Jerry Hays has been driving his 1968 Suburban for 40 years. A former gas station owner himself, Hays said he knows exactly how much gas the old truck holds: 20.5 gallons.

So when Hays started getting billed for several gallons more at gas stations around Marietta, he knew there was a problem.

“I was cheated, I know I was cheated. I’m paying for gas I wasn’t getting,” Hays said.

Records show that last year alone, more than 1,000 customers around Georgia complained to the state about getting ripped off at the pumps.

“We have to know that we are getting what we pay for,” said Sandra Glaze, staff attorney for Georgia Public Interest Research Group (PIRG), a local citizens’ watchdog organization.

The Department of Agriculture inspects more than 140,000 pumps around Georgia for things like measurement, calibration and quality, but the agency only has 24 inspectors for the entire state.

“It takes a long time to get around,” admitted Department of Agriculture Commissioner Tommy Irvin. “If we had more funding, we would get around much more frequently.”

There is no law requiring mandatory pump inspection times.

Inspectors say problems with pumps can err both ways: either giving you more or less than you paid for. It’s not always intentional, inspectors say.

Glaze said it is up to the Legislature to make sure that there are enough money and staff to protect consumers.

HERE ARE SOME WAYS TO PROTECT YOURSELF AT THE PUMP:

• Watch the pump to make sure it’s zeroed out and doesn’t jump once you start to pump.
• Make sure the pump has a recent inspection sticker. The sticker should be visible to the public.
• Don’t get gas while the supplier is filling the tanks. Wait at least a half hour or more to cut back on the possibility of air in the gas pumps.
• Get gas during the cooler hours of the day. Pumping early morning or late at night when the temperature drops could mean more product for your dollar.
• Report problems to the Department of Agriculture. Save your receipt and remember to write down the location and pump information.