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I think my gas tank shrunk.

Discussion in 'Gen 3 Prius Fuel Economy' started by Skoorbmax, Jul 7, 2010.

  1. Skoorbmax

    Skoorbmax Senior Member

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    When I got this 2010 back in March the dealer filled it. I remember clearly the range remaining was 591 miles. I understand this car has a 12 gallon tank and is rated at 48/51.

    I have gotten about 49 on every tank, give or take a little. However, the best I can ever do is 525 range left and generally it's around 510. I recently kept on going with the pump and actually had the tank overflowing, so believe me it was 100% full but the range was barely over 500 according to the trip computer.

    Does the computer learn or does it simply divide volume by ~50 to figure the remaining mileage?

    --

    Also, how accurate is the remaining range? This weekend I drove until it said 7 miles left, then it went from 7 left to 0 left. I finally got to a gas station about two miles later. Assuming my tank is not shrinking, the car's "zero miles left" actually must have around 1.5-2 gallons of fuel left, or another ~75 miles real driving.
     
    #1 Skoorbmax, Jul 7, 2010
  2. qbee42

    qbee42 My other car is a boat

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    The computer uses the gas tank sender unit to measure the amount of fuel in the tank. The sender unit is not very accurate on the Prius, or any other car for that matter. Remaining miles are calculated by simple multiplication of mileage times the remaining fuel. Don't expect too much accuracy from this estimate.

    Tom
     
    #2 qbee42, Jul 7, 2010
  3. tumbleweed

    tumbleweed Senior Member

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    Yes it learns, it uses the previous mileage to determine how far you can go, I don't know how far back it looks. Also on my car the miles to empty will be at zero about the time the last pip on the gas gauge starts to blink, at this point there is usually about 2 gallons left in the tank. Toyota doesn't want you to run out of gas. :)
     
    #3 tumbleweed, Jul 7, 2010
  4. Spenumatsa

    Spenumatsa Junior Member

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    Sorry if i sound ignorant, but where in the Multi display unit do i find the remaining range for gas. I had my Prius 2010 for less than a month and i am still learning about the various features in it.
     
    #4 Spenumatsa, Jul 7, 2010
  5. Skoorbmax

    Skoorbmax Senior Member

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    Press DISP on the steering wheel until you can see the little moving bar graph (although this isn't the only screenit works on) showing charge, throttle, pwr, etc. and then just press trip until you get to the text underneath the moving graph that shows a vehicle, a < sign, and then to the right of that the miles.

    I'm still wondering how the heck to turn the thing on with the "key" that pops out of the fob.
     
    #5 Skoorbmax, Jul 7, 2010
  6. walterm

    walterm Active Member

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    The metal key is actually only useful to open the driver's door in case of failure of the SKS system (for example if the fob battery dies). The fob has to be used to start the car, if its battery is dead you're supposed to be able to start the car by holding the fob against the Power button while you press it.
     
    #6 walterm, Jul 7, 2010
  7. Skoorbmax

    Skoorbmax Senior Member

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    Ah, thanks!
     
    #7 Skoorbmax, Jul 7, 2010
  8. tumbleweed

    tumbleweed Senior Member

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    Post deleted, question already answered.
     
    #8 tumbleweed, Jul 7, 2010
  9. EmuMessenger

    EmuMessenger New Member

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    This is strange for me as well. I show zero miles to empty, with the blinking pip, go to the gas station and the car takes 9 gallons. This is the third tank in a row with that behavior. Seems like I should have at least another 100 miles+ in the tank.
     
    #9 EmuMessenger, Jul 12, 2010
  10. andino

    andino Senior Member

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    I vaguely remember reading the manual that the tank is 10 gallons. Is that just a typo? I'm about to fill up for the first time tomorrow (down to 1 bar, no blink yet) so I'm just curious as to the actual size of the tank.
     
    #10 andino, Jul 12, 2010
  11. tumbleweed

    tumbleweed Senior Member

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    Owner's Manual page 558 says it holds 11.9 U.S. gallons. We should be able to go another 50 to 75 miles or so after it starts to blink and still have a reserve. But I have heard that the fuel pump (located in the bottom of the gas tank) depends on having some gas in the tank to help keep it cool.
     
    #11 tumbleweed, Jul 12, 2010
  12. andino

    andino Senior Member

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    ^^ Thanks. I guess I just misread it. I think the HSI says I can still go another 90 miles or so before empty. Hopefully I can make it through the day tomorrow before having to fill up haha
     
    #12 andino, Jul 12, 2010
  13. EmuMessenger

    EmuMessenger New Member

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    I may be wrong but I think the tank is supposed to be 11.9 gallons.
     
    #13 EmuMessenger, Jul 13, 2010
  14. 7odie7

    7odie7 New Member

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    It's 11.9 gallons. I've only filled up 4 times now and I just look at each mark on the fuel gauge as one gallon. It seems to be a 10 gallon fill up on the last mark, but I think it has a reserve that is beyond what the computer tells you.
     
    #14 7odie7, Jul 26, 2010
  15. Skoorbmax

    Skoorbmax Senior Member

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    So those who've filled up a few times or more what's the greatest remaining range you've seen? I cannot seem to break 525 and generally it's closer to 500.
     
    #15 Skoorbmax, Jul 26, 2010
  16. Colonel Ronson

    Colonel Ronson New Member

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    I saw 600+ miles remaining when i drove off the dealer lot.
     
    #16 Colonel Ronson, Jul 26, 2010
  17. Skoorbmax

    Skoorbmax Senior Member

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    See my first post, I had 591. I bet you never get 600+ again or even close. I think they put magic gas in at the dealer. I also wonder if perhaps there's a way to generate a higher estimate by not waiting until the gas is almost out. I generally fill up when 50-120 are left on the estimate.
     
    #17 Skoorbmax, Jul 26, 2010
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