Low coolant red flag?

Discussion in 'Prime Main Forum (2017-2022)' started by Johhhn, Feb 6, 2025 at 12:46 PM.

  1. Johhhn

    Johhhn Junior Member

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    i’m thinking of buying a used 21 prime out of state. So all I have to go on is pictures. On a photo of the engine bay I noticed that the coolant was below the low level (car salesman confirmed). Is this a red flag? My 2011 Prius has never dropped below full. Ever. Someone said it could be the heat exchanger? Wondering if I should avoid this car. Thanks for any input!
     
  2. BiomedO1

    BiomedO1 Senior Member

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    It may have never been topped off. Levels rise and fall with weather conditions and engine temperatures. If service personnel was just checking boxes, rather than doing their job - that can happen. Get the maintenance history/Carfax - anything that doesn't look right, walk away.

    Good Luck.....
     
  3. bisco

    bisco cookie crumbler

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    21 doesn’t have the exhaust coolant leak issue, but my 3 Prius never dropped coolant level in as many as 11 years
     
  4. Johhhn

    Johhhn Junior Member

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    car is in a desert so should be consistent temps, but even so, never seen that happen on my 2011. Only suspect stuff is that the carfax has irregular oil changes.
     
  5. Johhhn

    Johhhn Junior Member

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    really?? do you have a link somewhere? I was told it was all 4th gens??
     
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  6. bisco

    bisco cookie crumbler

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    Sorry, I don’t. Toyota upgraded the part when they discovered the problem and cause.
    The tsb should be in the sticky threads, and contain affected dates and vins.
    If not, you’d probably have to search the multiple threads here , it has been stated many times
     
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  7. Mendel Leisk

    Mendel Leisk Senior Member

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    Some "settling" is normal? From my 2010 third gen maintenance log:

    ====
    Friday, April 03, 2015
    km: 51198
    * changed engine oil and filter
    * lubed all hinges
    * checked both air filters (blew out and reinstalled, look good)
    * topped up both coolant reservoirs, both were near bottom line
    ====

    Then:

    ====
    Tuesday, October 23, 2018
    km: 77900~
    * Topped up engine coolant reservoir, it was nearing the low line. (Inverter coolant has not budged since last top up, still at the full line)
    ====

    Then:

    ====
    Thursday, October 15, 2020
    kms: 88155
    * changed engine oil and filter
    * changed engine and cabin air filters
    * changed engine and inverter coolant

    Haven't notice any drop in either, since.
     
  8. BiomedO1

    BiomedO1 Senior Member

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  9. Johhhn

    Johhhn Junior Member

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    Love your notes! talked to a Prius mechanic and he said there's a good chance the heat exchange exhaust thing is leaking and so if it is and the owner doesn't keep an eye on the coolant, it can affect the engine (obv). Which explains another 2022 I was looking at a few months ago that had low coolant also and the owner wasn't too surprised.
     
  10. Mendel Leisk

    Mendel Leisk Senior Member

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    The coolant leaks in the exhaust heat exchanger were remedied, for the the 2021/2022 model years. IIRC it was the earlier years of 4th gen, say 2016~2019. Basically it took toyota 3 effing years to wake up, acknowldedge the problem.
     
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  11. Johhhn

    Johhhn Junior Member

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    That's good to know, which means that '21 Prime being low on coolant and another '22 Prius also low, is definitely a red flag. Glad my spider senses were working!! :D