MPG indicator while driving is not consistent

Discussion in 'Gen 3 Prius Fuel Economy' started by srdamodaran, Aug 24, 2025 at 10:11 AM.

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  1. ASRDogman

    ASRDogman Senior Member

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    You have to replace the rings and pistons. They are the updated ones.
    You probably can't even get the older ones any longer.
    It would cost less money and work and time to get a remanufactured engine.

     
    #21 ASRDogman, Aug 26, 2025 at 10:58 AM
  2. Grit

    Grit Senior Member

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    Damn, saving gas cost Hell of a lot of
    Money!!!
     
    #22 Grit, Aug 26, 2025 at 11:46 PM
  3. srdamodaran

    srdamodaran New Member

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    If I had changed the oil at 5K instead of the recommended 10k, and gotten the piston rings for free under warranty, I wouldn't be having these problems...i think.
     
    #23 srdamodaran, Aug 27, 2025 at 6:43 AM
  4. Mendel Leisk

    Mendel Leisk MMX GEN III

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    Another option, especially if cylinder walls are deteriorating, is a new short block. Part cost around $2000~2500 USD. It will have new pistons and rings. It’s the component between upper oil pan and head gasket. Plus labour, maybe a grand?

    I believe this is the part no:

    11400-37140

    (part no determined on Amayama)

    Toyota USA parts site link:

    Short Block Assembly #11400-37140 | Autoparts.toyota.com
     
    #24 Mendel Leisk, Aug 27, 2025 at 7:20 AM
  5. srdamodaran

    srdamodaran New Member

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    I looked at this yesterday and saw some places selling for $1900.

    When I get the diagnostic, I will get them to check the Hybrid battery, the piston rings, HeadGasket, and the cylinder walls. Anything else?

    How do I know if a short block will be good enough or if I need a full replacement engine?

    Thanks.

     
    #25 srdamodaran, Aug 27, 2025 at 7:28 AM
  6. Mendel Leisk

    Mendel Leisk MMX GEN III

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    Yeah I’m also seeing one around $1950 USD.

    Short block is the “heart” of the engine. The next most significant component is the head, everything above head gasket. Machine shop typically provide a refurb service, clean, inspect and replace seals. @thecritic has a head gasket thread on his experience, linked in my signature.

    (on a phone turn it landscape to see signatures)
     
    #26 Mendel Leisk, Aug 27, 2025 at 7:36 AM
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