2012 Prius with 205K and Head Gasket Issues

Discussion in 'Gen 3 Prius Technical Discussion' started by ScottN427, Sep 4, 2025 at 9:47 AM.

  1. ScottN427

    ScottN427 New Member

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    New to this forum. As the title shows, we have a 2012 Prius with 205k miles and we now have what appears to be a head gasket issue. For those who too have encountered this, what is the typical 'success rate' of a head gasket replacement, and what are things to do and not do, products to use and not use? Did you have a shop do it, or did you DIY? Appreciate the feedback. The rest of the car is in really good shape. Thank you!!!
     
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  2. bisco

    bisco cookie crumbler

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    welcome!
    i haven't done it, but from what i've read, the most successful are those that do it right. meaning that all appropriate measurement and inspections are done to the rest of the engine before installing the new gasket and reassembly.
    all the best!
     
  3. ASRDogman

    ASRDogman Senior Member

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    Don't you have another feed where you pretty much said you had issues related to the head gasket?
    And were going to clean the egr system, and change water pump, etc.......

    It's not good to have two feeds on the same subject. It's too confusing.
     
  4. ScottN427

    ScottN427 New Member

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    No, I do not. I have never posted here before.
     
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  5. Brian1954

    Brian1954 Senior Member

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    The OP only has one thread created, this one. You are confused because there are three current threads created by three different users about possible head gasket problems. The other two threads, FYI, are linked below:
    https://priuschat.com/index.php?posts/3562520
    https://priuschat.com/index.php?posts/3562461
     
    #5 Brian1954, Sep 4, 2025 at 7:09 PM
    Last edited: Sep 4, 2025 at 7:16 PM
  6. ASRDogman

    ASRDogman Senior Member

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    I could be mistaken. It's very similar...
     
  7. rjparker

    rjparker Tu Humilde Sirviente

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    If it is an oil burner or it's been rattling for weeks on end or it has overheated you are better off with a rebuilt engine incorporating revised pistons, rings, egr and software. Especially if you want several more years out of the car.

    If it just started rattling, no overheating and no oil burning and you are looking for a shorter term before trading, try the head gasket.
     
  8. ScottN427

    ScottN427 New Member

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    That is where we are, it just started, and we have never had any oil burning issues....... I am thinking of giving it a whirl....... If anyone has suggestions on rebuilt head suppliers, gasket kits that are best, etc. Please advise..... :)
     
  9. DirkAshburn

    DirkAshburn Member

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    If you get the gasket replaced be sure to clean the EGR or you could very well be right back in the same place shortly after with a failed gasket again.
     
  10. rjparker

    rjparker Tu Humilde Sirviente

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    The Toyota rebuild kit is fine, it comes with a revised head gasket. Or you can buy that kit and also buy a felpro head gasket. Most would send their head to a quality machine shop and have it rebuilt. You know the history on your head; most others were driven for weeks or months. An alternative is to buy a new head.

    I would get the revised egr valve and have the ecu flashed to the latest code. If you change plugs, coils or water pumps use oem or Denso but not from Amazon or Ebay where counterfeits in fake packaging abound. Rock Auto is often the choice.

    Finally do not disconnect the orange ac compressor cable or it may cause a high voltage code later.
     
  11. ScottN427

    ScottN427 New Member

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    Thank you for the information and recommendations!!!
     
  12. Mendel Leisk

    Mendel Leisk MMX GEN III

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    There's a couple of head gasket related links in my signature. (on a phone turn it landscape to see signatures)

    You'd want to also ensure the Exhaust Gas Recirculation (EGR) system, including the EGR passages in intake manifold, get THOROUGHLY cleaned. Repeat every 50k miles thereafter.

    What the oil consumption like?
     
  13. ScottN427

    ScottN427 New Member

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    Thank you, I will watch the videos. It uses no oil between oil changes.
     
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  14. Mendel Leisk

    Mendel Leisk MMX GEN III

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    That's amazing; you must be doing something right. You do check the level?