# Dear Car Talk gas pump column

Ray,

Love your column and learn a lot of important information. Also feel a tie as my son graduated from MIT and also followed an unconventional career.

I live in Pennsylvania and buy my gas at a Giant food store because I receive gas points from shopping at Giant that are probably equal to \$.50/gallon. Giant also is at or near the lowest price in the area.

The problem is I suspect that Giant’s gas pumps are wrong and dispense less gas than is shown on the pump. Probably around 6% less.

First of all, when I pump the noise sounds like air is getting into the gas. Second, when I am near empty, I end up dispensing over 19 gallons of gas at a Giant store but only 18 gallons elsewhere. (I have 21.7 gallon tank with my 2012 Nissan Murano.) Third is that my miles per gallon reading on my dash when I fill my tank is always higher than if I calculate it by dividing my actual miles driven since the last fill-up by the amount actually dispensed. Over time, I would think these would average out.

The clincher was that I was in New Jersey and the dash said I only had 29 miles left before empty. I went to a gas station there and the pump automatically stopped at 17.976 gallons. I do not recall whether the person who pumped my gas topped it off. (It is illegal to pump your own gas in NJ.) The next time I needed gas the dash said I had only 30 miles left until empty. I filled up at Giant. The pump automatically stopped at 18.881, 0.881 higher than in NJ. I topped off the tank since I was getting \$.90/gallon off. The next time the pump automatically stopped was at 19.112 gallons.

Do you think the Giant pump is reading more than the amount of gas being pumped?
Should the pump automatically go to 18.881 gallons versus only 17.976 in NJ?
Shouldn’t the miles per gallon on my dash over time equal the amount calculated from actual miles driven and gas dispensed?
What is the legal amount the pump reading can be off?

Thank you.

Ed

First of all , I don’t think Ray will see this . Second , if you do really think the pumps are not accurate your state should have a number to call so they can be checked. Most states will have a sticker on the pump with the date it was last checked. Third , you method of checking is not really going to be accurate either. Fourth , why in the world are you letting your fuel level get so low anyway .

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Volvo, thank you. I will check the pump for last check date and see if there is a number there. My fuel level got low in NJ because I was in a rush for the birth of my first grandchild. I tend to let it go low in PA because I could \$ .90/gallon off on gas and waited until I was close to the Giant station. I guess my problem with letting it get too low is that any sediment in the tank may get to the filter? Obviously, besides running out of gas at the side of the road.

That is a possibility so why risk it. Also the fuel is a cooling agent for the fuel pump .

You can go here enter store name and county and get the last time it was inspected.

http://www.pda.state.pa.us/WMInspections/

I did not know about being a cooling agent for the fuel pump. How low can you go in the tank before affecting this?

It’s Me,
Thank you greatly. No records were found when I put in the gas station. But, this link led me to a website where I can file a complaint. I am going to file a complaint based on the info in my original question here.

Beyond the good suggestions that were already made, I just have to comment on…

Trust me, nobody is going to jump out from behind a tree and arrest you if you pump your own gas in NJ.
I’ve been pumping my own gas for ~50 years in NJ, and I have never even been chastised for doing it.
In fact, most gas attendants thank me for doing it!

VDCdriver,
My experience, which is very limited, has been different. The few times I have tried to pump my own gas the attendant runs over to me and tells me I cannot. I now do this when the attendant is slow so that I get service.

Ed
I appreciate that your experience may have been different, but–trust me–even if you ignore the attendant’s words and do it yourself, no harm will befall you.

Because if the attendant’s employer figures out that customers are pumping their own gas, the employer starts to wonder why he’s paying all that money for the attendant.

YOU won’t get in trouble. The attendant, on the other hand, stands to get fired.

Why don’t you just dispense some gas into a portable gas can, bring it home, and measure (outdoors, of course) how much you got?

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lion9car, thank you. I do not think I can measure accurately to 5%. 40 years ago my cousin in Georgia had a job checking gas stations. He had a special container that had a thin tube at the top to accurately measure the amount of gas dispensed.

Then why do they almost always thank me?
And, why are the same attendants there for months or years, despite my pumping of my own gas?

Because unless you’ve convinced everyone who shops there to pump their own gas, you’re an outlier.

It would have to vary from vehicle to vehicle but I just never let mine get below 1/2 mark. I live in Tornado alley so I want to be able to drive far enough to find a motel with power if need be . Just think about all those people in the Northeast US that might be setting with there vehicles running to keep warm on snow covered interstates. They really don’t need to run out of fuel.

I really don’t think gas pumps are off. States governments have a bureau that checks accuracy. I remember some 30 years ago that the house brand of motor oil was pulled. I think the cans were about 1% off. I had purchased a couple of cans and I never noticed that I was shorted.
I have no problem having my gasoline pumped for me. It gives someone work. Here in Indiana all stations are self service. My wife and I were traveling through some western state where the gas was pumped for us. I liked that. The attendants were friendly and it was interesting to talk to them.
Speaking of self service, I really dislike the automated check out at the grocery stores and stores like Walmart. These machines yell at me to “Place your item in the bagging area” while I am fumbling to try to open a plastic bag. If I move too slowly, it says “Speed it up you old geezer. There are others waiting to check out”. I like having a real person ringing up my items. Often the checkout people recognize me and will chat with me while ringing up the items. I am an old geezer, but I don’t like how impersonal the world seems to becoming.

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A calibrated container is the best method. The methods you described in your first post, are, to be frank, not at all accurate.

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It doesn’t have to be NIST traceable. Just take any 5 gallon gas can. It has a measurement molded into the container. Fill it to the mark and look at the pump. I’ve done this numerous times when I was curious if the station was off. Just get my lawn mower gas there and do this quick check. I’ve never found one that didn’t match almost perfectly…

Twin Turbo, thank you. I would have to buy a 5-gallon gas can to do. Use two 3-gallon gas cans now that are low profile where the height is small so they would not catch 5% either way.