1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Helicopter sound when starting?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Liz M, Feb 17, 2015.

  1. Liz M

    Liz M Junior Member

    Joined:
    Jun 9, 2014
    8
    1
    0
    Location:
    Albany, NY
    Vehicle:
    2010 Prius
    Model:
    IV
    This morning when I started my 2010 (30k miles, still a baby) it started making an AWFUL sound that I guess I can only compare to a helicopter (THUDTHUDTHUDTHUD). It was practically shaking the car. I panicked, shut it off, and tried again a minute later, at which point it was fine. I googled this and checked other threads, but the car was never in motion and the rear battery vent is completely clear. It drove in fine to work.

    It has been BRUTALLY cold for 2 weeks (up to -30 with wind chill) but last night was only -5 and it was a balmy 3 degrees this morning.

    Any thoughts as to what it was? If it doesn't happen again I won't bother taking it in, but I just want to understand what it was.

    Thank you in advance. I really appreciate this community.
     
    #1 Liz M, Feb 17, 2015
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    108,678
    49,379
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    normal. some unburnt fuel and condensation. this is a very common problem, and there are many threads here. there is a tsb for a redesigned intake manifold which you may want to explore with the dealer. it works for some, and doesn't for others. the best thing you can do for the car is never to power down while the engine is running. in the end, it sounds horrible, but no damage is being done.
     
    #2 bisco, Feb 17, 2015
    Liz M and The Electric Me like this.
  3. CR94

    CR94 Senior Member

    Joined:
    Dec 2, 2014
    2,642
    1,137
    0
    Location:
    Northwestern S.C.
    Vehicle:
    2011 Prius
    Model:
    Two
    How can we be certain no damage is being done?

    As it happens, I've never shut mine down while the engine was running---and never experienced that issue, so far.
     
    #3 CR94, Feb 17, 2015
  4. GregP507

    GregP507 Senior Member

    Joined:
    Apr 5, 2014
    3,002
    480
    0
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    I think backfire ignition is a very common problem with many engines, but we don't always hear it. I think it's possible to damage the exhaust, but this usually occurs only when it's already weakened by corrosion or other factors.
     
    #4 GregP507, Feb 17, 2015
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    108,678
    49,379
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    toyota promised us.:)
     
    #5 bisco, Feb 17, 2015
  6. Liz M

    Liz M Junior Member

    Joined:
    Jun 9, 2014
    8
    1
    0
    Location:
    Albany, NY
    Vehicle:
    2010 Prius
    Model:
    IV
    Thank you, that perfectly explains it as the last time I drove it was for 6 seconds to back it into the driveway turn around. Sorry I missed those threads- I suppose I shouldn't have been so specific about the type of sound.
     
    #6 Liz M, Feb 18, 2015
  7. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    108,678
    49,379
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    no problem, it's very disconcerting. all the best!(y)
     
    #7 bisco, Feb 18, 2015
(You must log in or sign up to post here.)