Faulty Check Valve Sometimes Cheats You, Sometimes Gas Stations

Meet the faulty check valve, a little gremlin that lives inside the gas pump. It could be pilfering your pennies. Or it could be pilfering the gas station’s. It really doesn’t care. According to an AP article, a faulty check valve inside a gas pump is difficult to diagnose and often goes ignored. The pricing errors it produces could either be in favor of the gas station or the consumer. How does this work?

The check valve’s job is to sync the gas flow of gas with the start of the price meter. A faulty check valve might produce a 2-6 second delay before the gas starts pumping, an error in favor of the gas station. Conversely, a faulty check valve could also start pumping a few seconds before the meter starts, an error that benefits the customer. Unfortunately, check valves are difficult to diagnose and may often work sporadically. A spokeswoman for New York’s weights and measures office said, “It’s very difficult to find it unless you are there every day several times a day.”

Making matters worse, many pumps are inspected too infrequently. The article says, “A New York Comptroller’s Office audit in 2000 found many municipalities statewide failed to inspect their pumps once a year as required 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.” State and local regulators doubt that most customers report gas pump discrepancies, and even if they do, it’s likely that they won’t get fixed.

So what can you do about faulty gas pumps? Try to keep track of how much gas your pump is actually pumping. If you see the price meter start several seconds before the gas flows, your pump may have a faulty check valve. Additionally, if you’ve put 11 gallons into your 10 gallon tank, it’s obvious that something is amiss. Report any discrepancies to the gas station. Some gas stations are authorized to give recompense if the discrepancy is within $5.00. Also look for a phone number on the side of the pump which you can use to report any problems. Don’t forget about your local Department of Weights and Measures since recent history has shown some positive results from their involvement.

Common glitch at pump adds to gas costs, also cheats station [AP]
(Photo: damageinc86)


Edit Your Comment

  1. thirdbase says:

    so you gas station owners write that check to the company that checks on the check valve to make sure everything checks out ok.

  2. akyiba says:

    The gas station I go to works in the consumer’s favor. Before you even press start the gas is already coming out.

  3. Lucky225 says:

    I just went to a gas station tonight here in Texas. Unlike California, if the shop is closed, usually the pumps are off, even tho they have a credit card reader on the pump. (Makes no sense, I know). Well I tried to purchase gas at one of these and the pump was off. However when I went to cancel the transaction it asked if I wanted a receipt? So I was like WTF? I hit print. The pump charged me 2 cents for 0.005 gallons.. Perhaps the evil check valve?!?

  4. Pro-Pain says:

    This is nowhere near as common a problem as they make it out to be. Usually only poorly maintained equipment will do this.

  5. brew400 says:

    Some gas stations are authorized to give recompense if the discrepancy is within $5.00.

    so if i put 18 gallons in my 17 gallon truck…. they will reimburse .5 a gallon

  6. Pasketti says:

    I routinely put in a gallon or so over the tank capacity, but I top off.

  7. StevieD says:

    The problem is a two way street…. overcharged and overdispersed.

    The problem with the valve occurs with high volume, poorly maintained equipment or very old, poorly maintained equipment.

    Best solution? Look for date of the last inspection on the state inspection sticker. A recently certified pump will have the greatest chance of being correct.

  8. jook says:

    A couple of days ago, I noticed that my gas started pumping a couple of seconds before the money counter started. I just shrugged and decided I was lucky at the time.
    It was an even better value because I was only buying $5 at the time, so I could go someplace cheaper down the line. That was about a gallon and a half?

  9. pfeng says:

    @brew400: I don’t understand how you get that number. They should refund the cost of the extra gallon of gas the pump claims it gave you but your vehicle clearly can’t hold. There’s no reason to do complicated math, or pro-rate it.

  10. @brew400: where do you live that gas costs $10/gallon?