My Gen.2 -Now only holds 31/2 gallons of gas in the tank bladder

Discussion in 'Gen 2 Prius Main Forum' started by ski.dive, Nov 14, 2025 at 3:43 PM.

  1. ski.dive

    ski.dive Active Member

    Joined:
    Jun 11, 2008
    964
    244
    0
    Location:
    Hutchinson Island,FL. Mt. Snow,VT
    Vehicle:
    2008 Prius
    I've had this 2008 Prius since new it has 137k miles:)

    But now my Gen.2 -Now only holds 3-1/2 gallons of gas in the gas tank bladder

    MY DRIVING RANGE IS ONLY ABOUT 140 MILES:(

    ***Long drives are no longer feasible.

    I'm thinking it's time to sell it.
     
    #1 ski.dive, Nov 14, 2025 at 3:43 PM
    Last edited: Nov 14, 2025 at 6:06 PM
    xw20_driver likes this.
  2. pasadena_commut

    pasadena_commut Senior Member

    Joined:
    May 2, 2019
    2,573
    764
    0
    Location:
    Southern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    I wonder in a situation like that if the rubber is just stiff or if there has been a leak and there are 6 gallons of gas between the bladder and the tank wall.
     
  3. Hayslayer

    Hayslayer Active Member

    Joined:
    Nov 6, 2024
    387
    216
    0
    Location:
    USA
    Vehicle:
    2009 Prius
    Model:
    Touring
    Are you happy with the car, other than the fuel tank? Is it in nice condition and worth keeping if not for the fuel tank? If so, maybe it's worth just replacing the fuel tank? Complete used assemblies are easily available if desired. I have a salvage yard about 20 miles from my house that actually offers mechanic services also, where they will install purchased parts for a reasonable fee. They have 2 lift bays and seem to stay fairly active. Maybe you could find something similar by calling around.

    Or do you have your eye on another car and this is a good enough reason to let it go and move on to something else?

    Both are reasonable options.
     
    #3 Hayslayer, Nov 14, 2025 at 8:55 PM
    Last edited: Nov 14, 2025 at 9:17 PM
  4. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    27,429
    18,014
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Sometimes, the pump nozzle shuts off early because of another issue somewhere in the onboard refueling vapor recovery (ORVR) system, and gets misattributed to the bladder because that's a part of the system that people have usually heard of.

    [​IMG]

    [​IMG]

    [​IMG]

    More info in this post and following.
     
    priumium likes this.
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    113,825
    51,807
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    still goes farther than a leaf...
     
  6. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    8,407
    4,281
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    I'm in agreement with ChapmanF.

    The bladder gets far too much blame for a lot of things. Having a car with no bladder, all the symptoms I've ever read about that are attributed to the bladder happen in our cars. So I would encourage people to drop these ideas and start thinking about what is actually going on.

    I have only read of just a few threads where the OP followed Chapman's train of thought and successfully fixed their problem. Interestingly, the faults were not the same, but nevertheless, they were in the fuel EVAP/ORVR in the back.
     
  7. pasadena_commut

    pasadena_commut Senior Member

    Joined:
    May 2, 2019
    2,573
    764
    0
    Location:
    Southern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Are there any DTCs on the OP's car? If not, is it known in what ways this system can fail so that the tank won't fill fully without setting one?

    I have seen that diagram before and I'm sure it makes sense if one already understands in detail how this system works. Me, I look at it and see what looks like an air tube starting at the fuel pump (the piece at the far right), it goes, up, left, up, left, then curves down into the filler neck. No valves Seems unlikely that the fuel pump has a direct connection to the outside air. I guess it wouldn't if the cap is on tight, then it would have a connection back into the gas tank. There are arrows showing flow in that tube from the filler neck, and from the pump. The arrows make sense I guess if the valves are open to the charcoal canister. If they aren't what happens? I suspect this is supposed to show that the air to flush the canister can come from either/both of those directions when the refuel check valve and the two purge valves are open, so that there is vacuum on the throttle body side of the canister.

    This was an interesting related read:

    Gas From Pump Slowly Goes In, Then It Spills Back Out (Part 2) | PriusChat
     
  8. xw20_driver

    xw20_driver Junior Member

    Joined:
    Feb 4, 2025
    85
    42
    0
    Location:
    PNW
    Vehicle:
    2007 Prius
    Model:
    Touring
    Does it make a difference if I fill the tank with the Prius powered off completely vs putting it in park but still in ready mode? I tend to fill the tank when it gets down to 2 or 1 pips but I always just put the car in PARK/READY. I do this with other ICE cars so I can watch the dash gauge fill up to full as the pump runs.
     
  9. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    8,407
    4,281
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    Best practice is to always switch a car off when refuelling. With the Prius specifically, it should be IG-OFF, not READY.
     
  10. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
    60,023
    41,250
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    There’s usually signs on the pumps, cautioning drivers to turn the car off.

    try googling:

    is it illegal to refuel your car while its running
     
  11. Moving Right Along

    Moving Right Along Senior Member

    Joined:
    Dec 29, 2016
    718
    574
    0
    Location:
    USA
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Unfortunately, that happens. But you’ve had it for a long time and it’s treated you well.
     
  12. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    12,884
    2,315
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Well got three at over 400K right now . Pull plastic cover over filling tubes in rear quarter I believe an astute individual might see the issue i see several but I don't have the issue I can drop 6.6 gal and sulqueexe in to 8.4 in a few more seconds been doing about 5 years now.looknst the fill and vapour pipes under plastic cover in rear quarter
     
  13. xw20_driver

    xw20_driver Junior Member

    Joined:
    Feb 4, 2025
    85
    42
    0
    Location:
    PNW
    Vehicle:
    2007 Prius
    Model:
    Touring
    I get that. On my ICE cars I turn off the engine but turn the ignition key back to on (not running). With the Prius, the engine is always stopped while I pump the gas.
     
  14. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    27,429
    18,014
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Look no further than the thread you linked to.

    The car does a regular self-test for leaks in the evap system, and will set codes for leakage, or for some conditions that interfere with that self-test. Beyond that, there isn't a lot of test coverage of the ORVR components. A glance at the diagram shows that many of them aren't electrical at all.

    This just ends up being another of the systems in the car where "it can't go wrong without a code" is an unfounded assumption.
     
  15. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
    60,023
    41,250
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    If it's in Ready, there's a good likelihood it'll run. Seriously, there's no upside to this. Other than "watching your gas gauge climb".

    WAC 296-56-60243:
     
    Tombukt2 likes this.
  16. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    12,884
    2,315
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    You know what you put in and your phone your app your brain know what ya takin out by miles on Trip!?. Put some sonic waves to the tank with the nice rubber mallet not to dent destroy . To shake up and move Internals . Be surprised how well this works
     
  17. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
    60,023
    41,250
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Is it possible to pump air into the bladder tank, reinflate it like a balloon? :coffee:
     
    xw20_driver likes this.
  18. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    113,825
    51,807
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    2012 didn't have a bladder, and never had the pumping issues the '04 and '08 had.
    still, that doesn't mean the bladder is the only possible cause
     
    #18 bisco, Nov 15, 2025 at 1:55 PM
    Last edited: Nov 15, 2025 at 2:51 PM
  19. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    12,884
    2,315
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    This is about a 2012 car oh cool now you should be able to run gas in it full tilt it almost any pump our persona and loaded 10 would take fuel. Like a pick. Up.
     
  20. xw20_driver

    xw20_driver Junior Member

    Joined:
    Feb 4, 2025
    85
    42
    0
    Location:
    PNW
    Vehicle:
    2007 Prius
    Model:
    Touring
    Came across this video yesterday about the 2nd gen Prius fuel tank system.