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Coolant loss after recent drain and fill?

Discussion in 'Gen 3 Prius Technical Discussion' started by Noahdoge, Jul 21, 2021.

  1. Noahdoge

    Noahdoge Active Member

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    Hello,

    Last week I changed both my inverter and engine coolant. I did only fill right above the low line as I thought the other line (middle connection line for engine side) was the “full”. Yesterday I noticed that the engine coolant dropped just a hair below the low so about 1 in. I topped it off to the actual full mark but now it has me worried. After driving on the highway for 25 minutes I opened the hood and used my flashlight to check all the vacuum lines, water pumps or any sign of coolant loss. I couldn’t find any evidence that there was any loss. Now I’m thinking I may have coolant leaking into the engine which could result in a blown head gasket.

    I just ordered all the equipment to clean/change the complete EGR system as well as intake manifold and set up an OCC. is this even worth doing since I probably have some kind of internal engine problems? Thinking about just selling the car and buying a used RAV4, unless you think I can fix it by doing all the EGR work.

    140,000 miles
    No codes
    No problems
    No knocking
    No oil burning or discolor
    New spark plugs
     
  2. bisco

    bisco cookie crumbler

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    i woud watch it for awhile before making a decision, it might be fine
     
    Mendel Leisk and Noahdoge like this.
  3. Noahdoge

    Noahdoge Active Member

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    Thanks! I’ll keep an eye on it daily. I haven’t found anything on how much is too much loss to point to the bad cylinder. It has knocked two or three times before, but that was in January, in 20*F weather. nothing else wrong with it.

    Does a clogged EGR/ intake manifold system cause loss of coolant?
     
  4. privilege

    privilege Active Member

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    a blown head gasket results in coolant leaking into the combustion chamber, not the other way around.

    check the coolant when the engine is completely warm (or completely cold) consistently.... don't church it cold one time, partially warm another and fully warm another.

    coolant expands
     
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    No. There's speculation that a clogged EGR system can lead to head gasket failure, and that often results in coolant loss, leakage into combustion chamber(s).

    Start with the low-hanging fruit: check the condition of the EGR pipe between EGR valve and intake manifold. @NutzAboutBolts video:



    A good way to check the head gasket is leak-down test.