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Are You Getting Taken At The Pumps?


Written by Alan Gionet

DENVER (CBS4)- "I don't know, I don't trust these things," said the man filling his car's gasoline tank at a filling station in Denver. Turns out, maybe he shouldn't be too worried. We checked out just how accurate things are and found we're actually getting a pretty good deal.

Inspector Robert Schlegel is one of ten inspectors who visit stations in Colorado. He says he generally finds them on the up and up.

"About 97 percent of the dispensers that we test, the meters are within tolerance," said Schlegel.

That means the amount of gasoline they put out is accurate to within allowable levels – gas pumps are allowed to be off up to six cubic inches per five gallons as long as the station averages no more than four cubic inches off, on average, on all of its pumps. There are 1155 cubic inches of gasoline in five gallons, so being off be a few isn't going to get you very far.

Now, here's the kicker; the vast majority are off in your favor. Only six or seven pumps in Colorado last year (the state couldn't confirm which number) were found to be shorting people of gasoline. But the amount was only by a penny or two per tank-full and the station operators were not fined. The pumps were recalibrated. Over 800 pumps were found to be off in favor of the consumer, meaning we were getting a little free gas. Again, not by much.

Not enough said Schlegel that he'd go out of his way to find a filling station that may be giving out extra gas.

"I'd know and I don't pay attention to that personally for filling up because it's not enough to make a difference," said Schlegel.

He also bottles gasoline samples for testing. They're taken to a state lab in north Denver operated by the Division of Oil and Public Safety under the Department of Labor and Employment. (Which remains an enigma to me as to why their operation would be under Labor and Employment – but I digress.)

Laboratory chemist Michael Charney takes calls from people who are worried they're getting ripped off and then asks inspectors like Schlegel to have a look. Charney is also confident of our fuel supply and said he hasn't found many egregious violators.

"Not that I'm aware of, I haven't seen it, I've been here three years, I haven't seen it," said Charney.

Now and then the gasoline samples he tests don't come up to par, but he doesn't think filling stations can get away with anything as insidious as adding water to gasoline. He pointed out that there would be vehicles that would stall out in a circle around the filling station, because they wouldn't get very far.

"If you put water in your gasoline it's just going to stall your car out. So a vendor can't do that and get away with it," said Charney.

He tests gasoline to make sure the summer and winter formulations are correct, that octane content is as advertised and that the banned additive MBTE is no longer in use. As to the octane content, he's had two samples fail so far this year. The problems he has discovered he attributes to human error, like bad mixing at the fuel racks, not the filling stations.

"Any problems I've seen so far have been just error, I mean error can happen," said Charney.

Honestly, it's not exactly what we expected to find. But neither do some of the people who call to complain and ask that filling stations be checked.

When Charney calls them back to give them results he said they don't always believe him, "Some people do, some people don't."

So you have to wonder about some popular questions. Like, let's say you have a 16 gallon tank and you somehow pump in 16.5 gallons. Why, we asked Schlegel? He told us the fuel tank in your car has air space at the top, to allow for expansion as cars go from hot to cold and cold to hot. Many stations he says have a slope next the pump. (Oh yeah, I thought as I looked closely at the ground where we stood at a Conoco near Kipling and Morrison.) That's why if you park your car on the side where the filling tube connects with the tank, you can fill into the air space, thus squeezing more into your tank.

"How you park, you're either going to put more fuel in, or less fuel in," said Schlegel.

That's why with different slopes, you may put more in at one filling station than another. Try parking with the fuel door on the other side of your car away from the pumps some time and if you can stretch the hose far enough to fill up (safely please) and you may end up putting in less because it's tilting the other way.

What about that sound I hear, I asked, when I begin to pump and it shows it's ringing up the big bucks and it doesn't seem like there's any gas going into the tank. Then I hear a click and I can feel the flow. Now it's pumping. What about that? Schlegel explained that when you start pumping gasoline, it is flowing, but as a slow rate at first – a safety feature. Then the click is the shift from low flow to high flow.

"So what happens is that you start your nozzle, doesn't seem like anything's happening and all of a sudden it kicks into high flow and you feel that nozzle and you can hear it," said Schlegel.

The reason is that the pumps have something called a gross line detector that is there to ensure that if there's a leak, it doesn't spread gasoline as quickly.

"If there were a large leak in the piping, it would never get the pressure up in the pipe and allow that into full flow," said Schlegel.

In low flow he told us, there's still gas coming out at far less than the typical 11 gallons per minute at high flow.

"And it was filling up, it was just doing that at a slower speed," said Schlegel.

No, I didn't catch the oil companies doing anything insidious this day. We seem to be getting our money's worth. In fact as pumps age, there's a greater likelihood that they're going to give us a wee bit more gasoline for our money. About all I could figure out, was look for the older pumps, but not enough to go out of the way. And inspectors like Schlegel also tell the stations when they're giving a lot away too. They probably don't wait very long to get them re-calibrated. A few cubic inches of extra gasoline aren't going to save your aching wallet from the high prices.

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