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Engine coolant level...

Discussion in 'Gen 3 Prius Technical Discussion' started by unigeezer, Sep 6, 2024.

  1. unigeezer

    unigeezer Member

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    If the engine coolant reservoir is a little bit below the full line, when the engine's cold, should I top it off to the "B" line, or do you do that only after draining and refilling?
     
    #1 unigeezer, Sep 6, 2024
    Last edited: Sep 6, 2024
  2. burebista

    burebista Active Member

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    AFAIK "B" line is only for draining and refill.
     
  3. ChapmanF

    ChapmanF Senior Member

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    Only as part of the refilling process after draining. It should end up at FULL after it has traded places with the air in the system.
     
  4. bisco

    bisco cookie crumbler

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    How many miles?
    Egr circuit been cleaned?
    Keep an eye on the coolant to make sure the head gasket isn’t blown
     
  5. unigeezer

    unigeezer Member

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    90k. And there is no way in hell that I would even attempt to pull that EGR valve out and all the work involved doing it! Especially if it's not showing any symptoms of being clogged or dirty.
     
    #5 unigeezer, Sep 6, 2024
    Last edited: Sep 6, 2024
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  6. bisco

    bisco cookie crumbler

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    I felt the same way, and traded it in when it started misfiring
     
  7. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Budget for a head gasket repair around 150k then, and another shortly thereafter, if the EGR is not cleaned at that time.
     
  8. Brian1954

    Brian1954 Senior Member

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    Only add coolant to the full line, which is just above the seam in the reservoir.
     
    #8 Brian1954, Sep 6, 2024
    Last edited: Sep 6, 2024
  9. unigeezer

    unigeezer Member

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    So, with only 90k, I would hazard a guess that I shouldn't have to deal with the EGR/manifold cleaning for at least another 30-40k, which would still put me 20-30k under that 150k threshold. And since my annual mileage is only around 5k, that gives me loads of time to put it off.
     
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  10. unigeezer

    unigeezer Member

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    Also, what about first just checking the EGR pipe, which is relatively easy to remove, and if that's clogged, it would be an indication that the whole EGR valve and manifold is likely clogged as well? And if the pipe is clean, save just being little dirty, would it then be likely that further cleaning wouldn't be necessary at that point?
     
    #10 unigeezer, Sep 7, 2024
    Last edited: Sep 7, 2024
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