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Lying Gas gauge

Discussion in 'Gen 2 Prius Main Forum' started by TorontoSusan, Nov 8, 2006.

  1. TorontoSusan

    TorontoSusan New Member

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    Last week, I got down to two bars on the gas gauge, and pulled into the gas station for my bi-weekly fillup. Yes, with the colder weather (and a couple of hilly trips) I noticed that my litres/km rating was a little high, but with only two bars showing I don't hesitate - after reading this site for a year, I've learned never let it go near empty.

    But jeez, when I filled up, I only put in 27 litres! Against a 45 litre gas tank! That means that although I only had two bars showing, I had a half a tank? What's up with that?
     
    #1 TorontoSusan, Nov 8, 2006
  2. Tideland Prius

    Tideland Prius Moderator of the North
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    Actually, 27 litres sounds about right.

    Two tanks ago, I pumped early (604 kms). I can't remember how many pips but it's definitely more than one pip left and I pumped 28 litres.

    On a blinking pip during summer, I'd pump 37 litres tops.

    Note that on Toyota cars without the bladder, Toyota sounds the warning when there's 10 litres left. We can't use that trick with the Prius because of the varying bladder size.

    However, just know that 27 litres is perfectly normal and fine.

    Besides, just smile and act smug when people see you stop, then glance at the pump and read 27 litres haha.
     
    #2 Tideland Prius, Nov 8, 2006
  3. oms2burn

    oms2burn New Member

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    <div class='quotetop'>QUOTE(TorontoSusan @ Nov 8 2006, 08:39 PM) [snapback]345951[/snapback]</div>
    There are a couple of threads in here on that (search on gas tank and/or fuel gauge). One recent one is:
    http://priuschat.com/index.php?showtopic=24809&st=0

    My summary: The gas gauge is pretty inconsistant, the bladder (tank) capacity varies by temperature.

    Personally, I fill up when I get down to two bars (usually smiling as the price climbs).
    -jack
     
    #3 oms2burn, Nov 8, 2006
  4. eagle33199

    eagle33199 Platinum Member

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    Like you said in the original post, it's better to be safe than sorry...

    Stupid bladder and cold weather.
     
    #4 eagle33199, Nov 9, 2006
  5. daniel

    daniel Cat Lovers Against the Bomb

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    The gas gauge (often called the guess gauge) is notoriously unreliable. Not really a big problem unless you feel you earn brownie points by going farther on a tankful. Fill early, and consider it a small price to pay for driving such a cool car.

    Of course, you'll never get the free bag of popcorn they give away with a ten-gallon (40 liter?) purchase.
     
    #5 daniel, Nov 9, 2006
  6. subarutoo

    subarutoo New Member

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    Every car I've ever had had a non-linear gage. The first half of the tank took a long time, while the second half dropped like a rock. The Prius is my first digital electronic gage, but all my analog mechanical gages were just about as in-accurate. I always fill up with 2-3 pips (every Thursday, unless I do extra week-end driving). Why worry about it?
     
    #6 subarutoo, Nov 9, 2006
  7. H2OSkier

    H2OSkier Member

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    I had a new one this week. Leave to go to work and I'm on two bars. No problem there is a easy access gas station just before work, maybe 35 miles. About 10 miles from home it drops to 1 bar. Again no problem. In less than 2 miles it starts blinking. So playing safe I go to the next closest station. I could only get 8.5 gals in the darn thing. The only gauge that is worse than this one is the one in my boat :)

    Ken
     
    #7 H2OSkier, Nov 9, 2006
  8. Charles Suitt

    Charles Suitt Senior Member

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    :eek: Your "GUESS gauge" is not lying. You just don't understand its language!

    I add fuel to my Prius usually when the gauge has one non-blinking pip, or sometimes sooner if the price is good and it's convenient. In two years, only twice have I had a "blinking" pip at which time I added fuel ASAP. The inconvenience and potential problems are far to great to risk in 'pushing' the fuel range. Perhaps this relates to my experience as a light aircraft pilot... you SURE don't want to run out of fuel aloft.
     
    #8 Charles Suitt, Nov 9, 2006
  9. Tideland Prius

    Tideland Prius Moderator of the North
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    <div class='quotetop'>QUOTE(subarutoo @ Nov 9 2006, 12:25 PM) [snapback]346461[/snapback]</div>
    Weird, mine's the opposite lol

    Aside from the first pip, the 2nd (or 9th, depending on how you're counting it) drops very soon after the first goes. After that, 3-5th drops every 50km and after the half tank mark, the rest of the pips drop after 80km lol. I've checked it all summer and it's fairly consistent. So basically, my first pip determines how far I'll go on my tank hahaha.

    Now that it's cooler, that doesn't apply any more :(
     
    #9 Tideland Prius, Nov 9, 2006
  10. daniel

    daniel Cat Lovers Against the Bomb

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    One nice thing about the CAN-View is that it can show the gas level in two-percent steps. While it's no more accurate than the guess gauge, it's far more precise. It actually goes up and down as I drive, but by watching those ups and downs I have a much better idea how much gas I actually have.

    I still fill up as soon as possible after the blinking, or sooner if convenient.
     
    #10 daniel, Nov 9, 2006
  11. TorontoSusan

    TorontoSusan New Member

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    ah, I've got it now! Forget the "gas gauge" stuff ... it's really an indicator to tell me when to fill up! (Actually, it's kinda cool ... God, I love this car.
     
    #11 TorontoSusan, Nov 9, 2006
  12. Sarge

    Sarge Senior Member

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    <div class='quotetop'>QUOTE(daniel @ Nov 9 2006, 07:31 PM) [snapback]346630[/snapback]</div>
    It would be cool if the Prius gas gauge also displayed fuel remaining in gallons or liters (or even % remaining) to be more precise, but that would probably look worse as it would fluctuate a little with the temperatures and as the fuel slushes around. ;)

    I remember my old Integra's analog gauge would sometimes go down as much as 1/4 tank or more on an extended right-turn such as an 270-degree turn on-ramp to a highway, at a 'spirited' speed. B) That car handled real nice!

    I've also only gone to the flashing pip twice since I've had the car, and both times filled up ASAP. Definitely not worth the risk of running out...
     
    #12 Sarge, Nov 10, 2006
  13. David Beale

    David Beale Senior Member

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    Get yourself a "Scangauge II". The trip functions include the ability to see how much fuel you have in the tank, how far you can go, etc. They base this on how much fuel has been injected into the engine, not on an unreliable sensor in the tank.
     
    #13 David Beale, Nov 10, 2006
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