Is the pic showing blown head gasket?

Discussion in 'Gen 3 Prius Technical Discussion' started by David Wallace, Jul 25, 2026 at 1:31 PM.

  1. David Wallace

    David Wallace New Member

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    Vehicle:
    2013 Prius
    Model:
    Two
    Hello,

    Wanted to ask for your help diagnosing potential head gasket on my 2013 Prius at 220K miles.

    *Please see attached view in cylinder 1 where I think I see coolant droplets?

    symptoms
    - slowly losing coolant from reservoir can’t find external leak
    - started with misfire (rattle) on cold starts then progressively moved to misfire shudder for 1-3 seconds every stoplight once engine heats up - otherwise drives normal avg 45-50 mgs
    - no codes (but did have p301 cyl 1 misfire months ago)
    - cyl 1 spark plug looked either lean or maybe a tiny bit washed

    tests
    - compression (cyl 1 - 120 with other 3 between that up to 130)
    - exhaust gas reservoir test (passed)
    -ignition coils passes

    What I’ve done
    - cleaned egr valve, cooler, pipe, and intake manifold
    - new spark plugs, air filter, oil change with filter, air filter
    - new injectors
     

    Attached Files:

  2. Mendel Leisk

    Mendel Leisk MMX GEN III

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    Vehicle:
    2010 Prius
    Model:
    Touring
    Was that the first EGR cleaning?

    QUOTE="David Wallace, post: 3620940, member: 223720"]started with misfire (rattle) on cold starts then progressively moved to misfire shudder for 1-3 seconds every stoplight once engine heats up - otherwise drives normal avg 45-50 mgs[/QUOTE]

    Very likely coolant in combustion chambers.
     
    #2 Mendel Leisk, Jul 26, 2026 at 3:28 PM
    Last edited: Jul 26, 2026 at 3:34 PM