Just how accurate are regular gas pumps? I wonder because it would be very easy to charge more than is actually being put in and no one would find out. Also, when one quickly sqeezes the handle to put in a few cents more I would think that the pump would have trouble putting that exact amount.
I would imagine that if a pump wasn’t accurate, people would soon notice… the tank would be taking in more litres/gallons than normal.
Dunno about the US, but in Canada, there’s a govt. agency that verifies things like that…
If you are worried about your gas pumps, you should also be worried about the scales at the grocery store. You need to find out which state agency regulates weights and measures and complain to them.
I’ve seen news reports about how some gas stations have pumps that’ll scam you. They under-pump in general, but are programmed to be accurate at, say, 5 gallon intervals, which is the amount usually pumped when they are being inspected for accuracy. So they can scam you and still pass inspection.
However, I really have no idea how wide spread this scam is.
Mongrel, if you want to put “a few cents more”, the pump will put “that exact amount”.
Peace
I once saw a program several years on 20/20 or 60 minutes. Apparently, there are government agencies all over that investigate complaints from people who feel they have been short changed. One Agency was stymied by repeated complaints from one location. Every time they got a fair count. It turned out that the pump meter would cheat after it passed the 5 gallon mark. Of course the agency was filling a 5 gallon can.
Apparently all it takes is some computer chip to cheat customers, not by much but enough to make a signicant difference over the day.
The next time you’re at the gas station take a good look at the pump. Chances are it will have an inspection sticker on it from whatever state agency is in charge of regultating them. It might be something like “The State Bureau of Weights and Measures” or the “State Department of Commerce.” Probably all pumps are tested at least once a year. If you have a problem, contact the state agency.
How about accuracy at the pumps when it comes to grades of gas? I’d like to think I’m getting something extra when I buy “plus” or “supreme”, but a small voice inside me tells me all I’m getting is ripped off.
The term we should be using here is calibration. Anyway, it is my understanding that, here in Ohio, the county auditor will calibrate and certify all gas pumps on a periodic basis. How? I dunno. Perhaps he/she fills up a calibrated volume and notes the readout. If the readout is within tolerance, it passes and the pump gets a calibration sticker.
In most states, I believe the State Dept. of Agriculture (or similar) is responsible for the accuracy of the pumps. Likewise, in most states, there is a Motor Fuel Tax Division or some such, likely in the tax/revenue agency, which is responsible for testing the grades of fuel.
Pumps in Virginia have a sticker like this. I’ve seen stickers saying that the pumps WERE NOT certified, also (funny that this non-certification was certified :)).
I’ve also heard stories of gas-station owners changing the pump software to pump out the correct amounts for standard calibration units (typically a 5 gallon amount is used by testers), but underpump for other amounts. The one I heard about via a news source was designed so that it underpumped below 5 gallons, AND above 5 gallons, but if you pumped in exactly 5 (or close to it), it was dead-on. This was to cheat people who just put in a dollar or two, and people who fill up the entire tank! If you happened to put close to 5 gallons (4-6 I suppose), you weren’t ripped off.
The gas station I heard about had been doing this for almost a year before the manager was caught by a state guy checking the pumps.
Arjuna34
contact these people, as well as these people.
The instance of the 5-gallon story I’m aware of was in California (the LA area, I belive) six to eight months ago (slightly longer, maybe?). In fact, the computers were programmed to pump exactly 5 gallons at 5 gallons, because that was the amount the Weights and Measures people used to check the calibration. At every other amount, the pumps overstated the actual amount pumped. It took some time and numerous visits to figure out what was going on.
Being that the guy who always says this hasn’t said it yet:
Gas pumps are not pumps! They are dispensers! The pumps are in the ground with the tanks.
Hush, you! It’s vernacular!
On the subject, let’s say the guy ahead of you pumped 87. You want 93. How much 87 do you get before the hose is full of 93? 1/2 gallon? Gallon?
–Tim
I always check the gas pump if I’m at a different station. I usually go to the same one, though, and they’ve always been accurate.
There’s an easy way to check, assuming you need 10 gallons or more, which is fairly common. Stop, or slow down and watch, the pump at the 10 gallon mark. If gas is $1.399, your total should be $13.99.
I also make it a habit to avoid stations that don’t let you pay at the pump. Those pumps (OK, dispensers), being newer, would likely be more accurate. The bottom line as a consumer is to never trust anyone. Always check, no matter what you’re buying.
Dire Wolf says:
Ok, so they charged you the right amount for 10 gallons of gas. Big deal. How does that indicate that 10 gallons of gas actually came out of the nozzle? Doesn’t it make sense that if they were lying to you about how much gas you get, they’d skew the price by the same amount? Otherwise, what’s the point?
That said, I have a hard time believing the stories about pumps which are designed to pump the right amount at 5-gallon intervals, but rip you off otherwise. That sort of capability would have to be built in all the way back at the original manufacturer of the pump (what, the gas station manager is reengineering the gas pump firmware? yeah, right). If the conspiracy runs that deep, any kind of certification is hopeless.
From this site:
I can’t get to the Times story, but I heard it on NPR [sub]so it must be true[/sub].
Wow, neat. I stand corrected.
<chevron commercial>
Do people really hack gas pump firmware to rip you off?
People do.
</chevron commercial>
I have noticed the following happening: When I mash the handle, the amount will advance to the 4 or 5 cent mark and THEN the gas will flow. Everytime I have reported this to the station clerk, I have gotten my nickel back. Once a guy tried to tell me that even though it did that, it was adjusted in the final cost and I got what I paid for. When I asked his name he gave me my nickel. Happened to any of you?
Q