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fuel gauge help

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by prius2go, Jul 24, 2012.

  1. prius2go

    prius2go Member

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    A few weeks ago the Prius had its annual service :)
    Afterwards the fuel economy improved, the fuel gauge seemed to hardly dropping at all. :)
    Stopped at the local garage to fill up with fuel and it took an extraordinary amount :(
    The tank was nearly empty. The slow realisation that the fuel gauge hadnt moved at all :(
    After filling the fuel gauge had moved to max :)
    A few hundred miles later it's so economical it's still at max :) :(

    What's happened?
     
  2. firepa63

    firepa63 Former Prius Owner

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    It's due to the bladder in the tank. The fuel gauge in the Gen II Prius is a "Guess Gauge".
     
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  3. prius2go

    prius2go Member

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    I think the sender is stuck - anyone taken one off and cleaned it?
     
  4. firepa63

    firepa63 Former Prius Owner

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    I doubt that the sender is stuck. It is located inside the tank and is not accessible. You just overfilled your tank and the gauge will eventually start registering.
     
  5. prius2go

    prius2go Member

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    Nope - I think it was stuck at about half full, I nearly used all the fuel but luckily filled up. Filling it up moved it to max. Its now stuck there - Ive done over 150 miles at 55mpg = 3 gallons. It should have moved. Is it inside the tank or bolted to the side?
     
  6. Rokeby

    Rokeby Member

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    It sure sounds like the fuel guage sender is gummied up.
    If this is so, it would not be good news.

    The fuel guage sender is integral with the fuel pump in a separate plastic
    subtank, separate from the fuel bladder. The problem is that both are encased
    in a steel fuel tank. To get to the sender you have to cut open the steel tank...
    with an air tool. The process is destructive and non-reversible.

    Here's the documentation:
    http://www.autoshop101.com/forms/Hybrid13.pdf
    the gas bladder: exposed! | PriusChat

    The answer then is to replace the tank, new or used.

    I'll leave it to your Googling skills to find one.

    Caution: Although replacement senders are available on the InterWeb, ~$100,
    for the life of me, I can't see how it alone could be replaced. And FWIW, the
    fuel pump goes for a mere $328:
    PartsTrain.com - Hard to Find Auto Parts and Truck Parts - Toyota Prius Fuel Pump
     
  7. prius2go

    prius2go Member

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    How difficult to replace the tank?
     
  8. RobertK

    RobertK Member

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  9. prius2go

    prius2go Member

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    I uldnt get it to work :(
     
  10. Rokeby

    Rokeby Member

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    AutoBeYours.com: 04 and newer Prius Parts Cars

    Psst! It would be helpful to know where you are...
    Completing the location info in your avatar would do fine.
     
  11. prius2go

    prius2go Member

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