fuel gauge

Discussion in 'Gen III 2010+ Prius Fuel Economy' started by GaryD1, Feb 13, 2011.

  1. GaryD1

    GaryD1 Junior Member

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    I'm down to one bar on 2011 prius, should I be seeing a blinking now or does that come later?
     
  2. amorris

    amorris Junior Member

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    On my 2010 it comes later.
     
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  3. Livi

    Livi New Member

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    Just got my 2011 and haven't seen any blinking or sounds. Went as far down as 34 miles till fill up. I heard it dings on 25.
     
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  4. Tink

    Tink New Member

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    Keep going. It will start blinking (& give a ding).
     
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  5. Paradox

    Paradox Prius Enthusiast / Moderator
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    It'll come on blinking when you have about 1.9 gallons left in the tank.
     
  6. fuzzy1

    fuzzy1 Senior Member

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    I will echo the advice to look at the Distance To Empty display. Based on watching closely for just a few events, my gauge reaches one bar at approximately 50 miles DTE, then starts blinking at exactly 25 miles DTE.

    Zero DTE is not really the bottom of the tank, simply the last warning, and even that warning appears only if one particular display is turned up. After that, you are on your own. While 1.9 gallons more appears to be typical, different individual cars will have different gauge errors. I believe one poster here ran dry just 7 miles after noticing DTE = 0.
     
  7. GaryD1

    GaryD1 Junior Member

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    This is exactly what happened with me, started blinking at 25 miles left to go. It held 10.15 gal
    This is the way I filled tank up. I ran in 8 gallons at full pump speed, then very slowly filled the tank until pump cut off, and stopped there. This is the way I'll fill tank from now on. I didn't get it full last fill up.
     
  8. vday

    vday Member

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    The few times I got down that low I found that the blinking starts after but sometimes it takes 30-35 klm and sometimes almost immediately.
    To figure out how much gas the car will take I use three pieces of info
    a. the gas gauge
    b. miles to refill
    c. consumption - MPG
    using all three I usually get it pretty exact.
     
  9. twittel

    twittel Senior Member

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    I have to tip my hat to you guys for your willingness to test the car's fuel limits. I've just never had the courage to drive near the edge of the fuel envelope and look across the chasm; it's too scary!
     
  10. Eagle 1

    Eagle 1 New Member

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    Gauge started blinking, showed 20 miles to empty. I drove 65 miles today after seeing the zero miles distance to empty...Really was counting on the other experts advice about the 1.9 gallons...LOL I was on highway with plenty of exits with gas stations..And I thought, what the hell; I could try out that SOS button...But I got scared and stopped to fill up. It still only took 10.9 gallons, so I could have gone a little further.
     
  11. patsparks

    patsparks An Aussie perspective

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    Why? Was petrol cheaper later in the day?
     
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  12. DumbMike

    DumbMike Active Member

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    I'm with you. I'm way too chicken to get close to running out of gas. So I appreciate what others have done to give me some indication of what limits I can push if it ever comes down to it.

    Didn't Bob Wilson do the experiment where he runs out of gas and sees how long he can run off the battery, or something like that? Yikes.

    Mike
     
  13. ksstathead

    ksstathead Active Member

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    The 2010/2011 won't go without gas, was what Bob found iirc. The gen2 would let you drive until it didn't have amps to give, reducing battery life.
     
  14. xs650

    xs650 Senior Member

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    My impression is that the onset of blinking is more erratic than the miles to empty number at low fuel levels blinking. If I'm driving gently without much braking and avoiding hard turns and hills, then it pretty consistently starts blinking at 20 miles although it has gotten as low as 18 miles once.

    A hard corner or steep slope can bring on blinking with close to 40 miles to empty but sometimes the blinking will stop if I drive several miles steadily before I get down to 20 miles to empty. It might also have involved a stop with the car off, I'm don't remember.

    My conclusion is that the miles to empty reading has a lot longer time constant (more damping) then the fuel gauge readout
     
  15. sub3marathonman

    sub3marathonman Active Member

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    I think that is what he initially said, then after much discussion and further testing he said that the Gen3 would go without gas, and wouldn't even tell you that it was out of gas. That is what he objected to. Here is the thread: http://priuschat.com/forums/gen-iii-2010-prius-main-forum/64211-warning-running-out-gas-gen-iii.html

    Now, at least from what I've heard, if you run out of gas in the Gen2 it will go while depleting the battery, but it will shift into N before the battery is harmed. At least that is what I've seen, oh, I mean I've heard. :)
     
  16. Lottamoxie

    Lottamoxie Finally! 12/29/2010 Prius IV

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    I unintentionally got to that blinking light because I hadn't noticed that my fuel was on 1 bar. It was showing 27 miles until empty. I admit I got nervous and took an exit off the freeway to get gas, though I was about 14 mi from home and my normal neighborhood gas station. I just didn't want to sweat out that last 14 miles, which involved some hills.
     
  17. fuzzy1

    fuzzy1 Senior Member

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    I must retract my "exactly 25" miles statement. After recently seeing someone else's observations of several different 20-something figures, today my gauge beeped and started blinking at 27 miles DTE. Tank average is reading 64 mpg.
     
  18. RRxing

    RRxing Senior Member

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    I'll leave it up to you as to whether it's scary or not, but it just doesn't make any sense to me.

    Besides the "fuel pump needs to be submerged to keep from overheating" argument, or the "you don't want to stir up any of the mung in the bottom of your tank" argument, miles per gallon is more important to me than miles per tank. No sense in trying to test the limits of something that has the potential to cause more serious problems.

    If a low oil pressure indicator comes on, is there anyone here who would deliberately keep driving to see how much further you could go before destroying the engine? How about low tire pressure?
     
  19. qbee42

    qbee42 My other car is a boat

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    Probably not, but my daughter did try it with a high temperature gauge on her Jeep. She made it several miles before the engine seized.

    :doh:

    Tom
     
  20. xs650

    xs650 Senior Member

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    If I didn't understand what either of those indications or the fuel level indicator meant, I would treat them and the fuel level indication equally.