Fuel gauge never goes to 9/10ths, anyone know what's wrong?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by richard13, Nov 5, 2010.

  1. richard13

    richard13 Junior Member

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    I have had my Prius for about 9 months now and I'm pretty consistent with fill ups. I let the gauge go to 1 or 2 pips and refill. However, I notice that a few days after refilling the fuel gauge goes directly from full (10/10) bars to 8/10 bars without stepping to 9/10 bars first.

    Has anyone else seen this? Know why this is happening or how i can be fixed? It's kind of annoying.

    Thanks!
     
    #1 richard13, Nov 5, 2010
  2. fuzzy1

    fuzzy1 Senior Member

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    The 9th bar is the shortest on my gauge, but it still goes roughly 60% of the distance of the other bars.
     
    #2 fuzzy1, Nov 5, 2010
  3. jdcollins5

    jdcollins5 Senior Member

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    I have not seen this on mine. I have not really paid attention to how long it stays on each bar but mine does step through each bar.
     
    #3 jdcollins5, Nov 5, 2010
  4. SmogSlide

    SmogSlide Member

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    Well, mine goes up and down when it is at the 9th bar. Whenever I restart the car, it goes back to 10/10 bars, and after some driving, it goes back down to 9th bar. Funny enough this behavioud does not occur at any other levels, only on the 9th.
     
    #4 SmogSlide, Nov 6, 2010
  5. fuzzy1

    fuzzy1 Senior Member

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    Mine does this from nearly any bar. It can even climb two bars, but the vast majority of them are from 8 to 10.
     
    #5 fuzzy1, Nov 6, 2010
  6. richard13

    richard13 Junior Member

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    Hmm... I've never seen mine go back up again, just down. Although, if these are similar to analog fuel gauges in other cars you'd think that would happen all the time.

    I am already planning on taking my Prius in for "rattle" service. I'll ask them about the fuel gauge too.
     
    #6 richard13, Nov 6, 2010
  7. fuzzy1

    fuzzy1 Senior Member

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    Everything I've heard indicates that the sender unit in the gas tank is the same.
     
    #7 fuzzy1, Nov 6, 2010
  8. rebenson

    rebenson Member

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    I usually get less on that bar as well. But I get more on full and usually have about a couple of gallons left on fill up. Wouldn't worry to much about it....
     
    #8 rebenson, Nov 16, 2010
  9. richard13

    richard13 Junior Member

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    Update:

    The dealer hooked my Prius up to the computer and it's not showing any faults and there's no software updates for my vehicle. That's ok, but when I asked about the float possibly being defective he said there wasn't one and started talking about a bladder in the gas tank. This made me wonder because I heard there was no bladder in the Gen IIIs. Can anyone confirm this with some documentation?

    Anyway, I filled my tank up again and low and behold my gauge dropped to 9/10 today at 65.8 miles (this sounds a little late). It stayed there until I got off the freeway about 8 miles later when it popped back up to 10/10. Maybe it's been doing this all along and I just haven't noticed? I'll have to see what it does tomorrow. I bet it will stick at 10/10 and drop down to 8/10 again. :mad:
     
    #9 richard13, Nov 16, 2010
  10. qbee42

    qbee42 My other car is a boat

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    The Gen III Prius has a sender unit, but no bladder. Your dealer is wrong, as they often are.

    Tom
     
    #10 qbee42, Nov 16, 2010
  11. cit1991

    cit1991 New Member

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    Mine kind-of does what you're describing. Sometimes I'll be on 8 bars, then after a long down-hill deceleration, it'll be back up to 10 bars.

    I can understand the fuel sloshing around and moving the sender up.

    But, it then stays at 10 bars for a long time. Then it drops back to 8 at once. This isn't the behavior I'd expect from dampening of the sender signal.

    I think the sender sticks a little bit. Not enough for me to complain about though.

    I use the 10x rule to fill up. I reset tripA at each refill. When the miles traveled = 10 x the average mileage, I fill up.
     
    #11 cit1991, Nov 17, 2010
  12. richard13

    richard13 Junior Member

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    So today when I started up my car I was surprised to find the gauge at 9/10 once again and after a while it went down to 8/10 (at 90 miles). I then toggled a bit back and forth from 8/10 to 9/10 and back. At 120 miles it first tapped 7/10 after which it toggled with 8/10s.

    I'll probably monitor the gauge and take note of the mileage the rest of this tank.

    I guess the bottom line here is that, after being more observant, my gauge is just like many others' who have participated in this thread. :) BTW, thanks to all of you.
     
    #12 richard13, Nov 18, 2010
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