High pitched whine when accelerating

Discussion in 'Gen II Prius Care, Maintenance and Troubleshooting' started by JMalmsteen, Jul 11, 2010.

  1. JMalmsteen

    JMalmsteen I love my Prius!

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    My car has 155k miles and I haven't had any previous issues with it. I noticed probably 30k miles ago the beginning of a whine sound when the car accelerates. The noise has been getting louder (it's really not that loud) but I am wondering if anyone knows what this could be. I want to avoid anything happening to the car and want to find out what the problem is so I can fix it. Thanks!!
     
  2. richard schumacher

    richard schumacher shortbus driver

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    That whine is normal. Hard to say why it was not noticed before. You can always take it to a dealer to see whether any "trouble codes" have been logged by the car. If there are none then no worries.
     
  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    If this is a new noise that is getting louder, maybe a transaxle bearing is beginning to wear out. If so, there's not much that can be done other than replacing the transaxle. That's a job that you should defer until the transaxle actually fails, due to the high four-digit cost involved.

    If you have not replaced the transaxle ATF fluid yet, you might do so now and see if that helps.
     
  4. edthefox5

    edthefox5 Senior Member

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    I have an 07 with 28K miles and I hear no whine when accelerating. In fact the car is very quiet except for the god awful tires.
    I thought the exact same thing as Patrick too mainly because of the high miles and you probably have never had the CVT Trans fluid replaced and your about 50,000 miles overdue. This fluid lubricates the bearings Patrick mentioned.
    Get that fluid changed immed. as its relatively cheap. 4 quarts of WS Fluid from the dealer and is mainly a diy. There are hundreds of posts here how to do it yourself. If dealer I have seen quotes here from $100 to 200.

    Alot of us here change that fluid diy every 30K to avoid exactly what you may be experiencing. I changed mine at 5K.

    Good Luck with it and report back.
     
  5. vertex

    vertex Active Member

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    Whine could be a bad bearing. You will not get any DTCs for that. Is it louder turning right or left during acceleration? Another possibility is a bad 1/2 shaft. The inverter whines under heavy load. If you lost some insulation under the hood you might be hearing that more then before. You can check if it is the inverter by opening the hood, ( so you can hear it better) when the ICE is running & charging the battery.
     
  6. Bob64

    Bob64 Sapphire of the Blue Sky

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    I've had this happen rarely, at low speeds. I think its the inverter whining.
     
  7. qbee42

    qbee42 My other car is a boat

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    Does your high pitched whine sound like this: "Slow down! Can't you see that car in front of us? I don't know why you have to drive so fast. I should have listened to my mother when she told me not to marry you. LOOK OUT! That truck is coming into our lane..."

    Tom