Do the rough cold starts hurt it?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Liz M, Oct 23, 2016.

  1. Liz M

    Liz M Junior Member

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    I've read a bit here on the forums about the cold soak starts for the Gen IIIs----I had one episode last winter where it sounded like a helicopter when I started it, and now that the temp is crashing her this week, my engine makes a bit of an angry sound (not terrible, but mildly concerning) until I speed up enough (around 20mph).

    My question is- does this hurt the car at all? If so, what can I do differently to prevent it? Wait til the engine goes quiet to turn it off?
     
  2. Raytheeagle

    Raytheeagle Senior Member

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    How many miles on your Prius? When does the sound happen, or what commonality would you say lends to the noise and rattle other than cold ambient temps? Are you moving driveway spots?

    Best to let the Prius go through its warm up cycle before pressing the power button to turn it off.
     
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  3. tankyuong

    tankyuong Senior Member

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    Btw it does harm the engine
     
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  4. Jimi1976

    Jimi1976 Active Member

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    What exactly is happening?
    What exactly do you think is being harmed?
     
  5. bisco

    bisco cookie crumbler

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    i don't think what you're hearing is a problem. the one episode you had is best to be avoided in the future, if at all possible.
     
  6. tankyuong

    tankyuong Senior Member

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    Continuous knocking will eventually blow a head gasket
     
  7. orenji

    orenji Senior Member

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    Always let the ICE shut down before turning off the car. This should solve any further engine knocking.
     
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  8. RichardScarry21

    RichardScarry21 Junior Member

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    Synthetic Oil (I recommend Mobil 1 0W-20) helps to some degree. As the oil is going to be less fluid during the cold starts, it's not getting to all parts of the engine as quickly. Synthetic oil is quicker to get to the entire engine.


    I don't know much about that sound.
     
  9. Mendel Leisk

    Mendel Leisk Underfoot

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    The one time I experienced knocking after start up was after cold-starting the previous day, and only running for a couple of seconds. This seems to be a cause-and-effect that a lot of owners experience.

    If you experience knocking at start up, I would suggest to immediately turn it off, wait a few seconds, and restart. This dispelled the knock for me, the one time I experienced it.

    And to (hopefully) avoid the situation, avoid the few-seconds-start-up-on-cold-engine.
     
  10. PriusNeckBeard

    PriusNeckBeard Active Member

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    So, regarding letting the engine complete it's cycle and turn off before turning the entire Prius off - is this just a 'common sense / sounds like a good idea', or do we know that this is best practice and why?

    Thx,
    - P
     
  11. Raytheeagle

    Raytheeagle Senior Member

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    Experience;).
     
  12. Mendel Leisk

    Mendel Leisk Underfoot

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    As mentioned above: the one time I've experience this knock at start up is after running the engine cold, for just a couple of seconds. Starting up the next morning: got the knock.
     
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