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2007 Prius Whirling/Vibration Noise Coming From Engine Compartment (w/audio)

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Alex G., Jun 27, 2014.

  1. Alex G.

    Alex G. Junior Member

    Joined:
    May 13, 2014
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    Location:
    Lindenhurst, New York
    Vehicle:
    2007 Prius
    Model:
    II
    Hi all,

    I had previously started a thread for my issue here but it's old now and I didn't have a video file to go along with it to help detail my noise issue. I would describe the noise as a whirling/vibration sound that can be heard as soon as the gas engine portion of the car kicks in (even in park) but gets louder and more noticeable as the car is in motion, especially at highway speeds (55 - 65mph). Opening the hood and listening to the engine block, the noise is definitely coming from around the area of the silver-covered portion by the driver's-side, which I believe is the hybrid synergy engine. The noise has gotten to the point where I really get bothered by it driving anywhere, and I have to turn up the radio to try to drown out the noise.

    Initially I took the car into a shop to have the wheel bearings looked at. I believe they only looked at the two front wheel bearings and determined the passenger-side front wheel bearing was falling apart. I had that replaced with a new bearing and they said the driver's-side front was fine. The noise was still noticeable as soon as I drove the car off the lot. I then took my car to the same Toyota dealer where I purchased my Prius where I've had a lot of maintenance performed there before. After looking the car over for a day (but only test-driving it for four miles) they told me there is absolutely no abnormal noise coming from the car that they could detect. That's impossible to me, because I know I'm noticing this annoying and prevalent noise now after seven years of driving this car without ever hearing it before. I should also note that I feel as though I can feel this vibration through the accelerator pedal. With my foot on the accelerator pedal I am fairly certain I can feel each individual vibration of this constant, long drawn out whirling sound.

    Any help would be greatly appreciated as now Toyota is basically saying I'm hearing things. Does this noise sound normal to you guys? I can post additional videos if necessary such as when the car is in park. I posted this video of me accelerating at highway speeds because this is the loudest the noise is at these speeds. Thanks for the help...


     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
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    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    The sound on your video does not seem abnormal but it is unclear how loud the noise is.

    Since the noise is being produced only when the gasoline engine is spinning, is it possible that the engine coolant pump bearing or the idler pulley is producing the sound?

    Do you have the opportunity to compare the sound produced by your car, with the sound produced by another 2G Prius?

    Have you checked the engine oil level?

    The shiny aluminum cover is over the inverter. The inverter typically will produce a high-pitched sound especially when the car is decelerating. There are no mechanical moving parts within the inverter, it is all electrical.

    The transaxle is located under the inverter and contains the two motor generators and power split device. When the car is sitting on the driveway and the gasoline engine is spinning, MG1 also will be spinning.
     
  3. insaner

    insaner Junior Member

    Joined:
    Dec 11, 2013
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    Location:
    Atlanta, GA and Huntsville, AL
    Vehicle:
    2007 Prius
    Model:
    N/A
    Mine is making a similar noise. Only happens when ice is engaged. Stops instantly when I take my foot off the accelerator. The sound is much more obvious at highway speeds. Did you ever figure anything out?
     
  4. sas0611

    sas0611 Member

    Joined:
    Mar 26, 2008
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    Vehicle:
    2008 Prius
    Model:
    N/A
    At around 20 seconds in I'm hearing something on top of the predominant droning noise. It sounds to me like it is pulley related - like on the waterpump assembly. I had a stethoscope on my waterpump assembly today and with the sound amplified it sounded a lot like what is going on at 20 seconds into your video. Maybe the pump is making that low pitched droning noise. I does sound like there is something else droning at lower frequencies. Almost sounds like how a snow tire would sound against the asphalt or how a cupped tired would sound. Id like to know what you find out because I am planning on taking my 08 in for front wheel bearings shortly. Like you, the sound appeared all of a sudden and immediately I was like 'What the hell is that'. When you've driven a vehicle for 9 years you know when something changes. I took my neighbor out to see whether he could identify the sound because he does a lot of his own work on his cars. He didn't hear anything unusual but I never took him over 40 miles/hour. Mine is way more noticeable 50 and above but I didn't know it when he was riding with me.
     
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
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    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    could a broken motor mount cause the sound?