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Don't trust your 'gas gauge'-Your gas tank bladder might be bad

Discussion in 'Gen 2 Prius Main Forum' started by ski.dive, Sep 5, 2024.

  1. ski.dive

    ski.dive Active Member

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    Yesterday my gas gauge went down to 'one blinking bar'-Almost running on empty.

    When I went to the gas station, I could only put in 6.5 gallons & the gas tank was full.

    I've heard about Prius owners not having an accurate gas gauge, because of the 'gas tank bladder'
     
  2. bisco

    bisco cookie crumbler

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    correct. as it stands, you don't know if the gauge is measuring lower or higher than expected.
     
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  3. MAX2

    MAX2 Member

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    Inside the metal tank there is a smaller plastic tank and a bunch of different pipes to control the fuel vapor recovery system and fuei pump.

    [​IMG]

    [​IMG]
    [​IMG]
     
  4. srellim234

    srellim234 Senior Member

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    Instead of a gas gauge we have a "guess gauge". I just stop and fill up when it's convenient after the gauge hits two bars or the miles on the trip meter hits 300 miles for the current tank. Absolutely no stress that way.
     
  5. ski.dive

    ski.dive Active Member

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    ***My gas started blinking-I only got 223 miles from my last fill up=Bladder is only allowing 6.5 gallons at fill up
     
  6. ski.dive

    ski.dive Active Member

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    ***My gas gauge started blinking:(
    -I only got 223 miles from my last fill up
    **Bladder is only allowing 6.5 gallons at fill up
     
  7. Tombukt2

    Tombukt2 Senior Member

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    That's not the bladder that's allowing or not allowing that The bladder is just there on top of the tank to help control fumes and outgassing of said fumes and vapors into the atmosphere The check valves and associated plumbing could be fubar and any of those valves that are closed when they should be open and so forth will cause this low filling The blinking business is possibly not related and is you're sending unit for the gas gauge they can blink for numerous reasons I'm guessing you're 12 volt and everything else is perfect so on the six and a half gallons you're going whatever the mileage you said above? Usually when this has happened to me and two of these cars I got under the car with a rubber mallet and banged on the bottom of the tank all around the bottom of the tank boom boom boom we're not trying to put huge dents in the tank or any dents in the tank or anything like that just trying to dislodge any garbage or crap that may be on the slider or whatever works the gas gauge float mechanism
     
  8. bisco

    bisco cookie crumbler

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    you'll never know if you filled up too soon, or ran out too soon.
     
  9. bisco

    bisco cookie crumbler

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    or it said it was empty when there were still 5 or 6 gallons left
     
  10. srellim234

    srellim234 Senior Member

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    That's why I fill up at two bars OR 300 miles. Fill quantities are very inconsistent with these cars.