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Transmission Shake due to Blown head gasket?

Discussion in 'Gen 3 Prius Technical Discussion' started by Ovib, Jun 2, 2020.

  1. Ovib

    Ovib New Member

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    I know i have a blown head gasket on my 2010 Prius.
    I also have a knocking at startup or at take off from stationary or low speeds.
    Mechanic said the knocking is from the transmission.

    My question is can this knocking be caused by the head gasket and not related to the transmission at all?
    The knocking started first. I cleaned the intake manifold and egr system than the gasket issued happend.

    Thanks
     
  2. PriusCamper

    PriusCamper Senior Member

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    Seems unlikely that a planetary gear transmission is going to be knocking? Not read of that before? Does mechanic work on Prius often?
     
  3. ChapmanF

    ChapmanF Senior Member

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    A misfiring engine works the living daylights out of all of the mechanical play available between all the parts of the transmission. First one way (bonk!) then the other way (bonk!) over and over and over.

    In between the engine and the transmission is a damper plate with little coil springs in it to soften some of the bonks. If the engine has been misfiring long enough, pieces of those springs are lying in the bottom of the bell housing, and now there are super bonks.
     
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    Uneducated and guarded answer: yes. But inferring from what @ChapmanF says: if you don't deal with the head gasket soon, there could be damage to the transmission, specifically that damper plate.

    How many miles on it?

    Thoroughly clean the full EGR circuit and intake manifold after dealing with the head gasket.
     
  5. tvpierce

    tvpierce Senior Member

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    I once had a knock so bad on my Gen-2 that it sounded like it was about to throw a rod though the block.

    Here's the video I posted at the time.



    You can see I'm crawling under the car listening and feeling... trying to determine where it was coming from. To me it sounded like it was coming from the transmission.

    The cause of all that racket: a bad ignition coil misfiring on cylinder-1. I changed that coil, and all was well.

    So yes, a misfire caused by a leaking head gasket can absolutely cause a knock.
     
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  6. ChapmanF

    ChapmanF Senior Member

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    Which makes it, by golly, a near-exact remake of this classic from 2011!
     
  7. Tombukt2

    Tombukt2 Senior Member

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    This is exactly whats going on in my head gasket repaired gen3 13 1.8 .. saying i need tech stream to diagnose further . im thinking a piece of carbon broke free whilst driving the 24 miles home from shop. is clogging up the elec egr valve .. i went from smooth running 63 mph.. too a knocking or rocking engine at speed. was shut dwn in seconds . all plugs including 2 look great no coolant med brown color . only 24 miles on them.
     
  8. mr_guy_mann

    mr_guy_mann Senior Member

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    Saying that it sounds as if you have a misfire- if the ecm set a misfire code then a scantool can help narrow down which cylinder has a problem. Still that wouldn't tell you the cause- could be lack of fuel or ignition, or some type of engine mechanical fault (compression loss or valvetrain).

    Posted via the PriusChat mobile app.
     
  9. Tombukt2

    Tombukt2 Senior Member

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    nO 2 HAS 0 compression dry test ..all others 109 sposed to be 150 engine time . wasted 800 on hg repair .. jdm engine 1000 delivered from japan ..