Watch out for cheating gas stations.

HappyDad

I'm going to check all the gas stations from now on when I refuel.

This is from an email I got from a friend.

There was a report that 1 out of 4 gas stations had calibrated their pumps to show more gas being pumped than what you actually got.

Here is how to check a pump to see if you are getting the right amount.

Whatever grade you are using, put EXACTLY 10 GALLONS in your tank, then look at the dollar amount. if the dollar amount isn't exactly 10 times the price of the fuel you have chosen, then the pump is rigged.

HappyDad

drwtsn32

Your proposed solution would not help identify the situation you describe.

If a pump was lying about how much gasoline was being pumped, the math (price per gallon calculation based on the display) would still be correct.

John Doe

Elsewhere

A reliable way to test for such a pump would be to bring two five-gallon tanks and fill them up.
If the pump does not agree, then the pump is rigged.

You need to test using more than five gallons because many of the rigged pumps are setup so they give the first five gallons correctly and then start "skimming off the top". This is because regulators go around and test using five-gallon tanks.

drwtsn32

I've heard that, elsewhere...but I'm not so sure that's just an urban legend.

Honestly, do the gas pumps even have the ability to be rigged in such a way? Seems like they would be highly regulated. Why would a manufacturer of such a pump design it with that ability?

Elsewhere

All of the modern gas pumps are computerized. Gas stations can buy rigged microchips and circuit boards for their pumps that will intelligently "throttle" the flow of gas at different times.

They can buy these things the same way people can buy rigged Dish Network cards to get free satellite TV.

Mad Dawg

The amount they dispense has to be adjustable so that if it is off, it can be brought back into tolerance.

drwtsn32

The amount they dispense has to be adjustable so that if it is off, it can be brought back into tolerance.

That does make sense, but it would be a static amount. It wouldn't adjust itself "on the fly." I have heard pumps that are rigged will dispense 5 or 10 gallons exactly correctly (since those are the amounts auditors check), but will cheat you on other amounts of fuel. Seems a tad far fetched to me.

Either way I'd be curious to see if any station has been verifiably busted for doing something like that.

inkling

Snopes:

http://www.snopes.com/politics/gasoline/cheating.asp

RubaDub

I have heard pumps that are rigged will dispense 5 or 10 gallons exactly correctly (since those are the amounts auditors check), but will cheat you on other amounts of fuel. Seems a tad far fetched to me.

Come on now ... "seems a tad far fetched to me." ???

It's just a matter of programming the computer chip to display whatever amount you want as the gas is flowing. The pump is still pumping the same, it's just the amount that is displaying that is modified.

I recall one case about a year ago where a gas station was busted for an illegal chip.

If you purchased under 5 gallons or any multple of 5 gallons (10, 15, 20, etc) the amount of fuel would be correct. After the first 5 gallons, it would slow slightly so that at the mid-points (7.5, 12.5, etc.) you would get ripped off the most (about a quart). By the time it would get to the next 5 gallon multiple, it would have "caught up" and displayed the proper amount. It was even programmed to "steal" more fuel based on your purchasing more (so if you thought you were buying 12.5 gallons, you were losing like 2 quarts).

The guy who got busted confessed that there is a big market for this type of thing and the chips are made to order based on how you want it to overcharge the buyers.

Rub a Dub

Watch out for cheating gas stations.

Share this