The Spies show you how to get more gas for the SAME money- Exclusive details and money saving tip!

With prices the way they are at the pump, it's painful enough.

But what you might not have known is that as the temperature heats up, less gas is going in your tank, hence the 'Hot Gas' syndrome.

Heat makes gasoline expand so if you fill up in the mid-afternoon when it's the hottest you are putting less gas in the tank.

US fuel pumps do not adjust for temperature, unlike their Canadian counterparts.

When the temperature of gasoline rises above 60 degrees, the gasoline expands but pumps don't account for the bigger volume and consumers receive less gasoline than they should. The technology to adjust for temperature has already been installed in Canada (since colder temperature gas costs the companies) but domestic oil companies have resisted because they made an extra $500 million in profits per year alone in California due to failure to adjust for gasoline temperature. Hawaii is the only state to adjust its pump calculations for hotter gas.

The Spies recommend filling up your vehicle early in the morning when temperatures are at their lowest in order to get the most for your money.

Lawmakers in California are looking into this 'Hot Gas' issue to see if anything can be done about it.

LexusNumberOne4ever - 5/10/2007 2:41:17 AM

+2 Boost

"The Spies recommend filling up your vehicle early in the morning when temperatures are at their lowest in order to get the most for your money."

Unless and untill you buy real large quantities of gas (more than tankful), the gains in price will be negligible.
Using this same logic, you should also avoid filling up your tank, in the summer at about afternoon/midday time.

Could anyone give the coefficent of thermal expansion of gasoline? I could calculate and tell you the precise gains.

Sachsi2 - 5/11/2007 1:32:48 AM

+1 Boost

Liquids expand and contract very little with temperature or pressure variations. By this logic you should also fill up on a rainy day as opposed to a sunny one because of the higher atmospheric pressure which in turn compresses the gasoline in the station's tank. By the way, letting the gasoline drip in completely before you pull the pump out will save you more than you 'lose' because of temperature-induced expansion.
Oh, and if you put the cap back on really quick you can also prevent some vaporization and that's going to save you a fortune as well.

"When the temperature of gasoline rises above 60 degrees, the gasoline expands ...". So it doesn't expand under 60F? If I remember correctly, the only liquid that expands with a drop in temperature is water between 0C and 4C.

Come on 001, get back to car news and commentary and leave these dumb "how to save gas the world" tips to politicians (especially to those in CA).

Cheers!

EnnNorak - 5/10/2007 8:56:27 AM

+2 Boost

Good tip for the truly frugal. Unfortunately it will not work for me as I live in Canada. Obviously the fair way to charge for gas is by weight which takes the temperature effect out of the equation but that would be totally impractical.

LexusNumberOne4ever - 5/10/2007 12:14:22 PM

+1 Boost

So people in Scandinavia or Canada are better off during winters? Could be!

investor27 - 5/10/2007 8:52:22 PM

+1 Boost

$500,000 million dollars is a lot of money, and the suggestion is not useless.

minimalist - 5/10/2007 9:43:51 PM

+1 Boost

the suggestion may not be totally useless, yet how useful is it to the average consumer when the estimated $500,000m is related to the profits to the oil companies as opposed to the costs to the average consumer?

it seems the costs to the average consumer whom do use this tip, which its convenience is questionable, is almost negligible.

minimalist - 5/10/2007 10:01:12 PM

+1 Boost

edit: i just noticed the article provides $500m as opposed to the post above indicating $500,000m.