2010 Prius making strange sound on start

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Joshua Smith, Sep 13, 2023.

  1. Joshua Smith

    Joshua Smith New Member

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    2010 Prius III started making a weird sound when we started it. Just got back from a trip from Charleston, SC to Asheville, NC and it had no problems, tried to start it the next morning for work and it was making a sound like this. 125k miles. Forgot about it for a few weeks and now the battery was dead but able to get this video.

     

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    #1 Joshua Smith, Sep 13, 2023
    Last edited: Sep 13, 2023
  2. Joshua Smith

    Joshua Smith New Member

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    #2 Joshua Smith, Sep 13, 2023
  3. bisco

    bisco cookie crumbler

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    have you cleaned the egr circuit?

    watch
     
    #3 bisco, Sep 13, 2023
  4. Joshua Smith

    Joshua Smith New Member

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    I have not, only got the Prius at about 105k and had not learned about it yet. Thanks for the tip.
     
    #4 Joshua Smith, Sep 13, 2023
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  5. JC91006

    JC91006 Senior Member

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    I hate to bring bad news, but you're on your way to needing a head gasket very soon. How is the coolant level on your car?
     
    #5 JC91006, Sep 14, 2023
  6. Joshua Smith

    Joshua Smith New Member

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    Coolant looks reasonable full and looks clean FWIW
     

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    #6 Joshua Smith, Sep 15, 2023
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  7. bisco

    bisco cookie crumbler

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    clean the throttle body and maf sensor, along with the egr.

    does she burn any oil?
     
    #7 bisco, Sep 15, 2023
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  8. Joshua Smith

    Joshua Smith New Member

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    Got a video under the hood after replacing the battery. Is this safe to drive about 10 minutes to have it serviced somewhere? It’s shaking pretty bad.
     
    #8 Joshua Smith, Sep 16, 2023
  9. Joshua Smith

    Joshua Smith New Member

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    Doesn’t seem like it, and oil level is good.
     
    #9 Joshua Smith, Sep 16, 2023
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  10. Mendel Leisk

    Mendel Leisk Senior Member

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    Probably blown head gasket. Get that resolved*, then deal with the EGR cleaning, including intake manifold. I've taken flak for advocating 50k mile interval for cleaning the EGR, so I've been saying 100K at the latest for first cleaning, then 50K thereafter. Thinking I'll go back to 50K from the get go.

    There's info on head gasket and EGR in my signature. On a phone turn it landscape to see signature.

    Don't use a head gasket sealer, will just compound your problem, or burn a purchaser.

    * Resolution could be:

    head gasket replacement
    engine replacement (with salvage)
    sell, with full disclosure
     
    #10 Mendel Leisk, Sep 16, 2023
  11. bisco

    bisco cookie crumbler

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    Yes, ten minutes should be fine
     
    #11 bisco, Sep 16, 2023
  12. Joshua Smith

    Joshua Smith New Member

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    Thank you all for the info, you’ve been very helpful.
     
    #12 Joshua Smith, Sep 16, 2023
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  13. MikeDee

    MikeDee Senior Member

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    People on this forum seem to be too quick to blame the headgasket. 125K miles? That seems a bit low for the headgasket to blow plus the coolant level is just a tad low. It could be the headgasket and that should be checked but there are other things that could cause the engine to misfire like injectors, ignition coil(s), and spark plugs for example.

    If the headgasket is starting to go, the engine should shake on a cold start but should stop as the engine heats up as thermal expansion compresses the gasket stopping the leak.

    Have the coolant and spark plugs been changed? If not, you're overdue. Are there any codes set?
     
    #13 MikeDee, Sep 16, 2023
    Last edited: Sep 16, 2023
  14. OptimusPriustus

    OptimusPriustus Active Member

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    Exactly. I had engine shaking and rattling like its going to blow up. I thought headgasket but fortunately checked the egr valve and it turned out to be stuck open. Installed new valve and car has been working fine thousands of kilometer. I did have CEL and EGR code though which made things easier.

    @Joshua, have you ever had the need to add coolant? During your ownership i mean. If not then i would start checking EGR valve. There is easy way to check if its stuck open
     
    #14 OptimusPriustus, Sep 19, 2023
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