Why do i get different fuel economy from different fuel companies in Utah?

Question

In Utah Maverik gas in usually 7-10 cents cheaper than the competitors, however, I've noticed that on average I travel 15-20 miles less on a full tank of Maverik gas. Is it possible that I'm not getting a full gallon of gas? Or am I getting diluted gas? How strictly does the Government regulate the quality of the gas coming out of pump. Is it worth saving 10 cents by going to Maverik as opposed to the other stations?

Answer 1

Most cars will travel about 300 miles on full 1 tank.  So your 15 - 20 miles difference is really about 5% to 7.5% variance.

That much could be for many reason (including cold weather when the car runs rich to warm it up, longer).

If you really want to measure mileage, don't just make "seat of the pant" estimates.  That will lead you to wrong conclusion.  Here's what you need to do to make sure:

(1) drive the car till it is almost completely out of gas.

(2) fill the tank (to the MAX) with gas from MAVERIK.

(2.1) reset the tripometer

(3) drive it on the highway on cruise (important)

(4) after about 30 to 60 miles (30 to 60 minutes.) get gas (MAX)

(5) note the MILEAGE on tripometer.

Now that is your MILES per GALLON.

Now do the same again using another gas.  Without good baseline you are not going to be able to make scientific judgement.

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The first poster says that cheap gas has "more" water.  That just stupidity.  Water and oil / gas do NOT mix.  If they poured water into THEIR tank, the water would sit on TOP.  They would be pumping gas till it runs out.  Then it would just water to the last customers.  

And YES the government does regulate those things.  I live in NYC and there are lots of gas stations that cheats their customers from time to time.  So they have city agency that makes sure that a gallon is really a gallon.

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The second poster said to get Amoco.  I also used to feel the same.  But I saw on History channel how gasoline is distributed.  ALL company pump their gas into ONE pipe line from texas to your local depot.  And then all their company TAKE the gas from the SAME ONE pipe line.  So it is ALL the same gas.  

Companies then add additive to change octanes, etc.  But they are the SAME gas.  And high OCTANE is not high quality.  The oil comapnies loves to call their gas "super" or "premium" to give the impression is it BETTER gas.  But NO! High octanes are just designed for high compression engines (like turbo engines)

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Good Luck

Answer 2

processing and additives make a difference. Octane levels.

We always referred to "cheap" gas as camel p*ss"

The best gas to buy is Sunoco. It  has always been  top of the line grade gas. Also  Shell . Trust me I have been driving for 40yrs an Always GO BACK to these gas companies.

You get what you pay for;  and with today's' high prices of gas  spend the extra few pennies and get the best!

Answer 3

You're probably buying an ethanol blend at the Maverik station. Look for a sticker on the pump that says 10% ethanol blend. Ethanol is a cleaner burning fuel but it also burns faster, decreasing your fuel economy. Most of the name brand fuels are not blended. The cost of the cheaper gas is sometimes offset by less MPG, so you aren't really saving much. My son has a Ford Ranger that is a flex fuel vehicle, meaning he can use gasoline, pure ethanol, or any combination of the two.  Ethanol is 40 to 50 cents a gallon cheaper, but he gets about 20 to 25% les fuel ecoomy.Some of the advantages to blended fuel though, is it pollutes less and is less susceptible to freezing.

Answer 4

I doubt if you are getting cheated on a full gallon of gas. The state usually has a weights and measures dept. that goes to gas stations to monitor gasoline flow and makes sure it meets the standards. Then a sticker is placed on the pump for that year. Also gas and water don't mix. Water is heavier than gas, so if you were pumping in any kind of water it would be the first thing the fuel pump would get since the fuel pickup is at the bottom of your tank. I agree with driving conditions also, however if you have been monitoring this for a while then you would see the consistancy you are talking about. I believe (and I am not familar with Utah) you are getting some ethanol in your cheaper gas OR you are getting a larger percentage of ethanol than the other gas station (I do not know if ethanol blends are mandated in your state as in others). Ethanol/alcohol will burn in your engine and gives it a higher octane rating, however ethanol has less energy (btu's) than gas, so fuel mileage will drop if you are getting an ethanol blend. Ethanol is added to the tanker when they bring the fuel. It does not come up a pipeline. So different companies can make their own blends in the tanker.

Answer 5

The cheaper gas has way more water in it than the expensive gas. The government doesnt really regulate it at all, as long as they are making a profit. It is very much worth it to pay for the more expensive gas because you fill up more often with the cheap c**p?! Whats 10 cents a gallon... to a whole take extra a week??

Answer 6

I do not believe the gas is diluted or contaminated or that the quality is inferior.   It must be the pump. Try using a different pump. The flow is regulated by the government but is not checked as frequently as we would like. Try a simple test filling a large container with gas in the different gas stations to be tested to ensure that you are getting the same amount of gas.