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Valve cover gasket and grommets at coils

Discussion in 'Gen 4 Prius Care, Maintenance and Troubleshooting' started by C-in-DC, Oct 2, 2023.

  1. C-in-DC

    C-in-DC Member

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    As part of an gen 4 to gen 3 engine swap, I found one coil was stuck inside the new-to-me engine. I was able to break the coil to remove it, replace it, and install new spark plugs.

    When I had a misfire due to a hole in the intake manifold, I took the car to a mechanic and he swapped the coils to check if one was bad. When he removed one of them it had tons of oil on it. Just recently, I realized now that that could indicate a leaking valve cover gasket and valve stem seal.

    The car has jolt forward a bit when the engine starts from time to time. Is that an indication that the above seals are at fault? Has anyone run into this issue with a gen 4? Do you recommend scoping the coil? fel pro or Oem to replace the gasket? Any permatex needed?
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    Might help:
     

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  3. C-in-DC

    C-in-DC Member

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    Thank you. I’m hoping the diagnosis is correct. Don’t want to throw parts at the car and not have any results other than fewer dollars in my pocket.
     
    Mendel Leisk likes this.
  4. C-in-DC

    C-in-DC Member

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    My scantool is recording misfires in cylinder 1 2 and 3 in the data stream but there’s no recorded code for the misfires I.e. nothing in the freeze frame. I can feel a jolt every now and then. Is there a min temp the engine has to run at?

    I’m seeing the engine run at 120 degrees f. I cut the jiggle pin and made a secondary hole. I’m wondering if that’s something you shouldn’t do on the East code because we get at or right below freezing temp. change thermostat housing?

    I’m also not seeing the egr step position in the data stream often. Is there a min temp for the egr to open?