Posted by Davoud on July 29, 2006, 5:41 am
richard schumacher wrote:
> The Prius counts fuel injector openings. The fuel injectors must be
> well-calibrated, otherwise combustion would not be well controlled and
> the emissions would be much worse.
OK.
> An alternate explanation for this discrepancy is that the gas pump is
> overstating the amount of fuel pumped. Considering that this means
> extra profit for the gas station, I decide to trust the Prius MFD.
Nope. Gas station owners are making sufficient profit that they aren't
willing to risk committing such a crime. They are subject to
unannounced visits by state weights-and-measures inspectors.
Davoud
--
usenet *at* davidillig dawt com
Posted by richard schumacher on July 29, 2006, 8:00 pm
wrote:
> > An alternate explanation for this discrepancy is that the gas pump is
> > overstating the amount of fuel pumped. Considering that this means
> > extra profit for the gas station, I decide to trust the Prius MFD.
>
> Nope. Gas station owners are making sufficient profit that they aren't
> willing to risk committing such a crime. They are subject to
> unannounced visits by state weights-and-measures inspectors.
The inspectors allow a certain amount of uncertainty. If by some funny
coincidence the gas pump always overstates the amount dispensed yet
remains within the allowed accuracy...
You may not have heard of a dodge that was common some years ago. The
inspectors always collected a certain quantity of gas into their
carefully calibrated container. The computer-controlled pump was set to
accurately display that certain quantity, but to overstate the amount
pumped for any other quantity.
Posted by Davoud on July 30, 2006, 3:30 am
Davoud:
> > Nope. Gas station owners are making sufficient profit that they aren't
> > willing to risk committing such a crime. They are subject to
> > unannounced visits by state weights-and-measures inspectors.
richard schumacher:
> You may not have heard of a dodge that was common some years ago. The
> inspectors always collected a certain quantity of gas into their
> carefully calibrated container. The computer-controlled pump was set to
> accurately display that certain quantity, but to overstate the amount
> pumped for any other quantity.
Yeah, I've heard that old wive's tale and, I think, all the others.
Davoud
--
usenet *at* davidillig dawt com
Posted by richard schumacher on July 31, 2006, 3:02 am
wrote:
> > You may not have heard of a dodge that was common some years ago. The
> > inspectors always collected a certain quantity of gas into their
> > carefully calibrated container. The computer-controlled pump was set to
> > accurately display that certain quantity, but to overstate the amount
> > pumped for any other quantity.
>
> Yeah, I've heard that old wive's tale and, I think, all the others.
Then you won't want to read this.
http://www.freelancestar.com/News/FLS/2001/052001/05312001/296679
Accuracy at the pump
Rising gas costs aren't the only problem for consumers. They could pay
too much just because they are tricked by the pump.
By KELBY HARTSON CARR
Date published: 5/31/2001
[...]
David Lazier, chief of the California division that oversees gas pumps,
said an investigation there led to about 30 stations being busted for
duping customers. Investigators in other states have unearthed similar
fraud.
In California, some stations were using equipment that tricked customers
into believing they were getting more gasoline.
"We do have a certain faction that feels they need to make an illicit
profit," he said.
The gas dealers were especially difficult to catch there because the
equipment initially fooled inspectors. While inspectors usually pump 1,
5 or 10 gallons of gasoline for testing, the illegal equipment ensured
those amounts dispensed properly.
"They were using our own test methods to beat us at our own games," he
said. "We started receiving enough complaints to lead us to believe
something was going on."
When undercover inspectors pumped differing amounts of gasoline--such as
6 or 9 gallons--they discovered they were shortchanged by as much as a
third.
He said savvy consumers can watch for such a scam.
For example, if a gas pump is rigged, the gauge that shows gallon
measurements will speed up right after the 1-, 5- and 10-gallon marks,
and go really slowly as they approach those points.
"You could actually see that speed up and slow down," he said.
He also said consumers should track their gas mileage and be concerned
if it suddenly plummets.
"If you notice all of a sudden you're getting a lot less miles per
gallon, that's usually an indicator," he said. "It could be a lower
octane fuel. It could be you're not getting everything you pay for."
[...]
Posted by Davoud on July 31, 2006, 4:37 am
Davoud:
> > Yeah, I've heard that old wive's tale and, I think, all the others.
richard schumacher:
> Then you won't want to read this.
> http://www.freelancestar.com/News/FLS/2001/052001/05312001/296679
Why not? It adds nothing to what I already knew; paraphrasing, it says
97 percent of pumps don't have a problem with the amount of gasoline
dispensed. The majority of those that are inaccurate err in favor of
the customer.
"This industry is very highly regulated."
""It's not a regular practice that we find. I've never seen anyone
tampering."
My point is that tampering is rare.
> Accuracy at the pump
>
> Rising gas costs aren't the only problem for consumers. They could pay
> too much just because they are tricked by the pump.
>
> By KELBY HARTSON CARR
> Date published: 5/31/2001
> David Lazier, chief of the California division that oversees gas pumps,
> said an investigation there led to about 30 stations being busted for
> duping customers. Investigators in other states have unearthed similar
> fraud...
30 stations in California? Out of how many thousands? My point is that
tampering is rare.
Davoud
--
usenet *at* davidillig dawt com
> well-calibrated, otherwise combustion would not be well controlled and
> the emissions would be much worse.
OK.
> An alternate explanation for this discrepancy is that the gas pump is
> overstating the amount of fuel pumped. Considering that this means
> extra profit for the gas station, I decide to trust the Prius MFD.