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EGR Cooler leaking into engine?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Ovib, Jun 13, 2020.

  1. Ovib

    Ovib New Member

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    I'm getting the classic head gasket symptoms. Loosing coolant, white smoke, engine rattle, missfires.

    The symptoms started happening after I cleaned the EGR cooler. Is it possible that I have damaged the EGR cooler and it is now leaking coolant into the engine and triggering the same symptoms as a head gasket?

    Would the EGR valve prevent the coolant from entering the intake and engine?

    How can I diagnose if the EGR cooler is leaking?

    Thanks
     
    #1 Ovib, Jun 13, 2020
  2. mjoo

    mjoo Senior Member

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    I don't know how likely that is. I suppose the only way to tell would be to remove the EGR cooler and pressure test the coolant pipes.

    It's more likely a head gasket, exhaust heat recuperator leaking, or loose/rotting hose IMHO. The EHR leak is common on Gen 4 and due to a bad weld.

    Pixel XL ?
     
    #2 mjoo, Jun 13, 2020
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  3. fuzzy1

    fuzzy1 Senior Member

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    If the EGR cooler is leaking, wouldn't this show signs inside the EGR pipe? This pipe is fairly easy to remove for inspection.

    If you didn't shove any strong or hard pointy objects into the EGR cooler during cleaning, it seems quite unlikely that it could be leaking coolant into the EGR flow.

    ==========

    FWIW, I cleaned my EGR cooler and pipe in late December. Then did intake manifold yesterday and today, along with changing PCV valve, and installing a hose loop for an OCC. But now I need either a smaller OCC to fit up high, or get up the motivation to install the one in hand down on the lower frame.
     
    #3 fuzzy1, Jun 13, 2020
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  4. Georgina Rudkus

    Georgina Rudkus Senior Member

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    Could be that the OP failed to install one of the gaskets correctly.
     
    #4 Georgina Rudkus, Jun 14, 2020
  5. Ovib

    Ovib New Member

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    That's what I was thinking of doing. Remove the EGR pipe and start the engine and see if there is any fluid coming out?

    Is that a good idea? Do I have to plug the whole on the intake manifold?

    I did use a wire to clean some of the hard build up, maybe that could have damaged the coils inside?

    What's is the "OP"?
     
    #5 Ovib, Jun 14, 2020
    Last edited by a moderator: Jun 14, 2020
  6. fuzzy1

    fuzzy1 Senior Member

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    Which gasket? I'm not thinking of any that could lead to such a leak path.
    I'd hope that any signs of stray fluid would be visible inside the pipe, without even starting the engine
    I thought they were stamped fins spot welded to a wall, not coils. So any leaks would have to be punctures or tears on that wall.

    But then my EGR cooler was not caked enough to need a wire or mechanical action, just repeated soaks and flushes. Others with more severe clogging might have looked closer at the internal construction.
    Original Post(er). Either post #1 of a thread, or the person who posted it. In this case, you.
     
    #6 fuzzy1, Jun 14, 2020
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  7. tankyuong

    tankyuong Senior Member

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    Purely coincidence doubt it’s leaking
     
    #7 tankyuong, Jun 14, 2020
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