1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Lost 10mpg after EGR clean, etc. Now losing mind!

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by FriedCells, Oct 12, 2020.

  1. FriedCells

    FriedCells Member

    Joined:
    Jun 26, 2020
    95
    72
    0
    Location:
    San Diego, CA
    Vehicle:
    2011 Prius
    Model:
    IV
    Just an update on that problem. It is fixed! Thank God! I updated that thread as to what happened there. Now, hoping that maybe the new O2 sensor, and very clean injectors will bring back my lost mpg's.... Will update after a few tanks of gas.. hopefully just solved everything at the same time with a brief 3 days of utter terror and despair. :eek::oops::confused::mad::cry:...but soon....:):cool::D:LOL:(y)
     
  2. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,103
    4,032
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    (y)(y)(y)(y)(y)
     
    FriedCells likes this.
  3. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,834
    3,136
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    So, replacing one of the O2 sensors go the car to start? And kept it running?
    Or was it dirty injectors?
     
  4. FriedCells

    FriedCells Member

    Joined:
    Jun 26, 2020
    95
    72
    0
    Location:
    San Diego, CA
    Vehicle:
    2011 Prius
    Model:
    IV
    I know you saw the answer in the other thread, but will answer here anyways in case anybody ever reads it in the future. New O2 sensor and cleaned injectors was still giving me a no-start situation. I had flooded the engine through a series of unfortunate events....
     
    ASRDogman likes this.
  5. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,834
    3,136
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    Yeppers.... :)
    All that unburnt fuel will screw up the O2 readings. Did you change the sensor?
    You might not have needed too. But since you got it..... :)
     
  6. FriedCells

    FriedCells Member

    Joined:
    Jun 26, 2020
    95
    72
    0
    Location:
    San Diego, CA
    Vehicle:
    2011 Prius
    Model:
    IV
    Yeah, I had gotten the O2 sensor anyways before the flooded engine issue as some readings led me to believe that the O2 sensor was possibly on it's way out, leading to my reduced mpg's.
     
    ASRDogman likes this.
  7. Abarnabe

    Abarnabe Member

    Joined:
    Jan 7, 2018
    88
    58
    0
    Location:
    Netherlands
    Vehicle:
    2010 Prius
    Model:
    III
    Thanks Mendel. My bad, I didn't read carefully, so troubles are below 1 cm and way above 0. When I filled mine I used an electric pump and exceeded the max level, it was a bloody mess.

    The first time I did it at 100k km there was nothing coming out of the upper hole, which confused me quite a bit. I assume the 3.5 quarts toyota advises to put in should be lower than 0 mm or my car was leaking, but I haven't seen any.
     
    #87 Abarnabe, Nov 16, 2020
    Last edited: Nov 16, 2020
    Mendel Leisk likes this.
  8. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,834
    3,136
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    If the vehicle is level, it's extremely hard to overfill the transmission.
    You would have to really want to overfill it. But if you have 4 qts, and put them in,
    it will likely be leaking out.
     
    Mendel Leisk likes this.
  9. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,470
    38,103
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Yeah I've replaced the fluid 3 times now, resolved to lay off, might be good for the duration. I raise and level the car (safely), drain, fill with funnel/hose, and it invariably starts overflowing a little past 3.5 liters.

    I would recommend using freshly opened bottles of Toyota ATF WS (Toyota recomedation), replace the drain and fill bolt washers, torque is 29 ft/lb.

    It's very easy to do thus, impossible to screw up.
     
    Abarnabe likes this.
  10. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,834
    3,136
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    OH NO!!! You just HAD to type that didn't you??? :whistle::eek:
     
    FriedCells and Mendel Leisk like this.
  11. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,103
    4,032
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    o_O
     
    FriedCells likes this.
  12. Abarnabe

    Abarnabe Member

    Joined:
    Jan 7, 2018
    88
    58
    0
    Location:
    Netherlands
    Vehicle:
    2010 Prius
    Model:
    III
    I recycle the washers by polishing them with 400 followed by 800 sandpaper on a flat surface.
    I have polished away my finger too and can't unlock the cellphone anymore :rolleyes:
     

    Attached Files:

    #92 Abarnabe, Nov 17, 2020
    Last edited: Nov 17, 2020
    Mendel Leisk and SFO like this.
  13. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,470
    38,103
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    How much would replacement washers be for you? Here they are kinda insane, IIRC almost $3 CDN apiece. But when it's every five years or so??
     
    Abarnabe likes this.
  14. Abarnabe

    Abarnabe Member

    Joined:
    Jan 7, 2018
    88
    58
    0
    Location:
    Netherlands
    Vehicle:
    2010 Prius
    Model:
    III
    Here they cost 2.50 euro, about the same price, but the dealer don't keep them on stock, he said he has never changed transmission oil to any gen 2/3 and none of them failed so far. The last time I have ordered washers it took 3 or more days, I lost one and I couldn't wait other 3 days, so polishing was the fastest option for me.
     
    Mendel Leisk and royrose like this.
  15. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,834
    3,136
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    I've changed mine 3 times and have not changed either one. Neither is leaking.
     
    Abarnabe likes this.
  16. FriedCells

    FriedCells Member

    Joined:
    Jun 26, 2020
    95
    72
    0
    Location:
    San Diego, CA
    Vehicle:
    2011 Prius
    Model:
    IV
    Just in case anybody ever reads this thread this far in search of answers, I still don't have one. I'm still getting 42mpg avg over last 1,500+ miles.... I finally gave in and took it to a local mechanic that only works on Prius. They have been there for many years, 4.9 star reviews locally, they lease and exclusively work on these cars. I showed them the list of things that I did to the car. They practically offered me a job! Lol. They were amazed at the list of things that I have done and said it's exactly the list of things that they would have done. They looked over the things, did some diagnostics with Techstream and could not find anything wrong. Their only suggestions were that maybe the engine is losing it's efficiency because of the piston rings, compression loss, or the HV battery or both. They said that even though I reconditioned the battery, 1 bad module can bring the whole pack down, and my load tests were not sufficient as you need to load test for several hours to truly check the condition of each module. Said that even though my battery is lasting a lot longer now, the power still may not be getting generated properly from the battery if there are weak modules.
    So they suggested to just keep driving it until I get a code or the engine or battery craps out. They said if there were an issue with vacuum or fuel pump or anything like that, that I'd get a code. So, I've just come to accept, reluctantly, that 42mpg is my new normal :(
     
    douglasjre likes this.
  17. wheezyglider

    wheezyglider Active Member

    Joined:
    Mar 12, 2011
    247
    177
    0
    Location:
    SF Bay Area
    Vehicle:
    2010 Prius
    Model:
    Five
    Oh man that's agony. I can't believe there's no way to collect hard diagnostic data that would point towards the cause or at least rule out *something*. I guess if you could actually swap batteries with your sister's car and drive both on that test run again, it would definitively judge the battery.
     
    FriedCells likes this.
  18. FriedCells

    FriedCells Member

    Joined:
    Jun 26, 2020
    95
    72
    0
    Location:
    San Diego, CA
    Vehicle:
    2011 Prius
    Model:
    IV
    Yeah, that might help, but honestly, I have no desire left to figure it out. I have spent 100's of hours trying to figure it out. And the Prius specialty mechanic also had no answers without going irrationally deep and expensively into taking everything apart. There's no obvious answer at this point, and I've just come to accept that, and keep getting my 42mpg's. I'm completely burnt out from working on it.
     
    douglasjre and Mendel Leisk like this.
  19. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,470
    38,103
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Fried?
     
    FriedCells likes this.
  20. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
    5,286
    4,225
    0
    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    42 is fairly normal on 17s, but it looks like you might be on 15s. Have a Festivus attitude, and accept any offered blessing from @Grit.
     
    FriedCells likes this.