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[SOLVED for $0] -- 2010 misfire, stumbling, stuttering, coolant loss, head gasket, etc. symptoms

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Atari, Mar 16, 2019.

  1. The Critic

    The Critic Resident Critic

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    The only problem with this solution is that the coolant may boil. A 50/50 solution of antifreeze will not boil until 223F, but only if it is pressurized to 15 psi. By removing pressure from the system you are effectively lowering the boiling point to 212F.

    The Prius normally runs at about 190F - 195F and the temp creeps up under certain conditions. 212F does not provide you with a very large margin.
     
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  2. sam spade 2

    sam spade 2 Senior Member

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    LOL. He "invented" nothing.

    Ever since the week after pressurized cooling systems were invented........about 100 years ago......mechanics quickly figured out that not allowing the system to come up to pressure would eliminate or minimize a coolant leak and allow you to still drive.......for a while.
     
  3. sam spade 2

    sam spade 2 Senior Member

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    You have the right idea but I think your numbers are off a bit.
    I think 223 is the boiling point at one atmosphere (no added pressure) and with 15 PSI it goes up to about 240.
     
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  4. The Critic

    The Critic Resident Critic

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    You’re right. That number should be a bit higher under 15 psi. I googled and 223F was the number I found, but it seemed a bit low for 50/50.
     
  5. Kambo

    Kambo Junior Member

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    I would love to know if there was any side effects to this fix, I have 2012 PriusV I been notcing my coolant level has been dropping the car seems to struggle unless its in power mode can someone give definant answer to this problem everyone is facing it cant be just as simple as removing the orgin from the coolant resevoir
     
  6. sam spade 2

    sam spade 2 Senior Member

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    You are right. It isn't that simple.
    Leaving the pressure cap ajar so that no pressure builds up is only an EMERGENCY measure to let you limp off of the highway and into a shop.
    Doing that often results in a violent boil-over if you drive fairly hard and then slow down or stop.

    There is no magic. If you have a coolant leak you need to find the leak and fix it right.
    If coolant is leaking into your crankcase oil, and you continue to drive it like that........your engine eventually is likely to be damaged, beyond an inexpensive repair.

    P.S. And not everybody has that kind of a problem. Far from it.
     
  7. Drew Michael

    Drew Michael New Member

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    Just did that today using 1/2 of a 38 oz bottle of Bar’s Leaks Sealer with carbon fibers. Worked as described. No more engine shake or cylinder #1 misfires or radiator coolant disapearibg
     
  8. waldox

    waldox Junior Member

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    drew, how is your bars leak seal holding up after a year and how many miles on it so far with the fix?
     
  9. waldox

    waldox Junior Member

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    how did it go long term after removing the coolant o ring?
    how often do you need to top off the coolant?
    how did it perform in the summer?


     
  10. mr_guy_mann

    mr_guy_mann Senior Member

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    What happens with one person's car has little to do with someone else's. There are lots of variables: ambient temperature, car use (flat or hills, traffic or highway, A/C or not, EGR condition, how "bad" the H/G leakage is, etc). So the short form is, it will last until it doesn't.

    Posted via the PriusChat mobile app.
     
  11. Tommy West

    Tommy West Junior Member

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    How long did this car last?