Angry about the price of gas? Just imagine paying for gas you don't get.
Some alert consumers have noticed it over the years: A pump that seems to hesitate a second when the lever is squeezed. Anywhere from 2 to 6 cents tick off before the rush of gasoline starts. That's what happens with a common, hard to diagnose and mostly ignored problem with the "check valve," which is supposed to make sure gas flows at the same time the price meter starts.
But even if your gas pump works, it can still be off as much as $5 for every fillup. Tests by local regulators allow a pump to charge as much as 6 cents more than the gas delivered in a five-gallon test, but there can be wild fluctuations. Federal regulators said they had heard of swings of as much as 30 to 40 cents per gallon.
Don't blame the gas guys. Even consumer advocates say retailers may be losing as often as consumers and no one appears able to rig the meters. But the small "check valve" at the end of the multibillion dollar industry just wears out, and often goes unnoticed for months.
Regulators' records show short staffing, particularly for financially struggling counties that try to inspect pumps every six months, but too often don't even meet the one-year requirement in states like New York.
Federal standards require all gas pumps to start pumping gas as soon as the price meter starts, said Ken Butcher of the National Institute of Standards of Technology, part of the U.S. Commerce Department.
Bob Wolfram knew something was wrong when the pump he used in Davenport, Iowa, showed he put two more gallons of gas into his tank than the tank holds.
"I was low, but it wasn't negative," said Wolfram, a 54-year-old engineer.
He reported it to a consumer Web site then took it to the government regulators, who acted promptly. But even then, the test showed the pump was only off a quart.
"I just kind of said, `What will they do next?'" Wolfram said.
Correcting the problem depends on alert, well-informed consumers like Wolfram. It also depends on honest retailers who choose to pass along reports to regulators who must confirm the problem before an authorized repair company is called to fix it.
"There's one Mobil owner, he tells clerks that if there's a discrepancy within $5 to reimburse the customer," said C. Todd Godlewski, director of the Schenectady County Bureau of Weights and Measures in upstate New York, the agency that inspects pumps.
"Yes, it can be that much," he said.
A bad valve can also work against retailers, freezing the price gauge for an instant after gas starts. No one's sure who gets gored more, or how deeply.
"Even one penny on the amount of petroleum pumped annually or weekly at a station would be several thousand gallons of fuel, and add that up," Godlewski said. "If you have a meter that is costing a customer, it adds up quite a bit."
The problem compounds the aggravation of record high gas prices. On Thursday, the national average hit a record $3.556 per gallon, according to a survey of stations by AAA and the Oil Price Information Service. That's nearly 71 cents higher than last year, and rising.
"We'll hear complaints about this quite regularly, usually several each week," said Jason Toews, co-founder of the independent nationwide Web site GasBuddy.com that tracks prices and complaints.
"It's mostly about the principle of it," he said. He said the problem usually only costs a consumer pennies per fill-up, but that's more than enough these days.
Toews discounts the conspiracy theories that blame the problem on retailers or the oil industry. Most retailers, he said, wouldn't know how to alter the pumps to their benefit.
A New York Comptroller's Office audit in 2000 found "many municipalities" statewide failed to inspect their pumps once a year as required (the best practice is two inspections every year) and that meters were corrected during testing, which could mask overcharging. Four years later, a follow-up audit found only partial resolution, partly because of too little staffing.
Bob Renkes of the Petroleum Equipment Institute based in Tulsa, Okla., has heard about complaints, "mostly when gas prices are high." He said meters "get looser over time," which could make them malfunction and start to count pennies before fuel starts pumping.
"I think our industry would love to replace anything that wears down," Renkes said. But the check valves aren't a high priority when the industry is dealing with issues such as preventing identity theft when swipe cards are used, static electricity discharges and the 5 percent of retailers whose old mechanical equipment can't register a price of $4 a gallon.
State and local regulators doubt any but the most ambitious consumers would contact them in case of a problem, even though the phone numbers are on inspection stickers. More likely, consumers fume and wonder if they were cheated, or report it to the manager of the gas station or convenience store.
"That's what's tough about this," said Jessica Chittenden, spokeswoman for New York's weights and measures office that oversees local inspectors. "The two cents or whatever would go to the retailer."
Even when a report is made, and a local inspector is dispatched, the problem might not be fixed.
Chittenden said a faulty valve would likely work sporadically: "It's very difficult to find it unless you are there every day several times a day."
Godlewski, the upstate New York inspector, said he's found pumps off by as much as three times the 6-cent threshold. Because of it, his county this year is tracking pump problems and hopes to quantify it for the first time.
"You ask yourself," he said, "`If nobody said anything ... and it's run like that for six months, how many were taken?'"