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Misleading fuel guage near empty

Discussion in 'Gen 3 Prius Technical Discussion' started by cagauss, Apr 10, 2011.

  1. rrolff

    rrolff Prius Surgeon

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    Distance is a well documented 'feature'. When the gas bar starts blinking, set a new trip odometer to 0. I always get 50MPG, so that means I can go 100 miles. I never fill up before 70. Ran out once not paying attention - but fortunately had enough battery + coast to get me into the station...
     
  2. kgall

    kgall Active Member

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    This is interesting, because when my car beeps at me it says 20 miles remaining. I wonder why the difference?

    And for the OP, I join you in saying that I fill up with about 10 gallons when the thing reaches 0, and everyone else in saying this means there's about 2 gallons left. More or less.
     
  3. 32kcolors

    32kcolors Senior Member

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    It isn't just misleading near empty but throughout the whole range. I've had it jump up or down two bars. A rep said it best that it's supposed to be neither accurate nor inaccurate.
     
  4. ReDave

    ReDave Junior Member

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    I think part of the problem, at least for me, is the digital fuel gauge. I've owned and driven lots of cars, but this is the first one I've driven with a digital gauge. All of the other cars I've driven, the gauge goes below empty. And the cars I've owned I've learned where "empty" really is, you can't do that with digital. You can make educated guesses based on current tank MPG, but you don't have a visual guide that has a 'real' stopping point. I put about 500 miles or so a week, and my previous car [03 Matrix] had to be filled up twice a week, what a pain, so i pushed it as much as i could, and... never 'ran' out of gas [i did coast to a gas station once or twice lol] I'll just have to learn how far i can go, and be good with that.

    It is a blast driving this car, and my 1st tank was 57 'indicated' MPG [54.5 calculated based on miles and assuming the dealer really filled it up]
    2nd tank 54 ish indicated and 51.5 calculated.
    Working on my 3rd tank now.
    Driving this is quite the blast, BTW. I got a SGII and love fiddling with all the readouts, driving the wife mad. In fact I think I've sorta scared her from driving it, unfortunately. I've tried to convince her, that all my machinations are un-necessarily, and her 'mileage' won't be held against her, she's not quite believing that you really can just push the button and drive away....
     
  5. Gurple42

    Gurple42 New Member

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    Simple solution, when you get down to 3 bars, fuel up as soon as you can, then don't worry about it!:rolleyes:
     
  6. 32kcolors

    32kcolors Senior Member

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    3 bars are way too much fuel. Do it at 1 bar.
     
  7. pakitt

    pakitt Senior Member

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    I agree - I calculated that in my case (i.e. my average fuel consumption) when it beeps (1 bar) I have still about 200km to "dry". When it starts beeping, I start looking for a gas station, never before.
     
  8. F8L

    F8L Protecting Habitat & AG Lands

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    I agree as well. I used to fuel up when I first got down to 2 bars. This generally put me at about 350 miles for the tank. I recently started fueling up at 1 bar or as soon as it starts blinking. This puts me at about 430miles with the 17s or 500+ with the OEM 15s.
     
  9. fuzzy1

    fuzzy1 Senior Member

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    Depends on the situation. Commuting in excellent weather, I have no qualms about going 40-50 miles past the flashing pip (in a Gen3 only, not a Gen2). Going skiing during avalanche season -- more than once we haven't been able to return home on the same mountain highway or even the same day -- I refill before leaving town even at 6 bars, or the equivalent on the other car.
     
  10. eltee

    eltee New Member

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    I was initially annoyed at this as well... It is important they notify you early, I understand that. The problem is that once they notify you, there is no further indication at all of how much range you actually really have before there's a problem.

    I can do some pretty far out mountain driving, and there may not be a gas station for 50+ miles even on some otherwise relatively large roads/passes up here.

    My improvised solution has been pretty simple... take one of the two trip gauges and use it as a tank gauge. It tells you your current fuel economy, and you know you have roughly close to a 12 gallon tank. toss in a little fudge factor like never want to use the last gallon and a little over-estimation, and yer good to go.

    i.e. if its saying 50mpg, and 500 miles driven (even if the flashing dot and miles remaining have been 0 for a while), you have a guess of maybe 25 miles remaining before hitting that 'last gallon'.
     
  11. Bootjacker

    Bootjacker New Member

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    The manual says you have 1.6 gallons left. I average 45 mpg. To be safe, I figure 1.5 gal X 40 mpg and find a station within 60 miles.