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Car feels like it's braking when I'm not

Discussion in 'Gen 2 Prius Technical Discussion' started by XNak20, Jun 30, 2013.

  1. XNak20

    XNak20 Junior Member

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    I'm not sure if stalling is the correct term for this issue, but this is what's happening: a few times I'll be driving and when I take my foot off the gas pedal my car will make some weird noise and start slowing down really fast without me touching the brake pedal. This isn't a constant problem, I think it's only happened a few times in the last few months. For what it's worth, this has only happened while driving on the freeway. I have no idea what could be causing this, has anyone here experience a similar problem? Also it's a 2005 prius if that changes anything
     
    #1 XNak20, Jun 30, 2013
  2. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    The Prius cruise control attempts to regulate your speed, if you have cruise on 60 MPH but speed up to 70, it will haul you back to 60 fairly rapidly.
     
    #2 JimboPalmer, Jun 30, 2013
  3. XNak20

    XNak20 Junior Member

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    My bad, I meant braking. It just starts slowing down really fast when I take my foot off the gas,. It's not on cruise control (as far as I know), it does this no matter what speed I'm at
     
    #3 XNak20, Jun 30, 2013
  4. bisco

    bisco cookie crumbler

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    did you just get the car? perhaps you're not used to regen which occurs when you release the gas pedal. try just slightly depressing it to see if it speeds up. you can look at the power display to see what's happening, but keep your eyes on the road!
     
    #4 bisco, Jun 30, 2013
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  5. moshe1436

    moshe1436 Bought used.

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    Make certain your emergency brake isn't even slightly engaged. This happened to me with my '07 Prius when I noticed I was slowing down when descending fairly steep grades.
     
    #5 moshe1436, Jun 30, 2013
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  6. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Is it possible that your gear selector is in B, when this happens??
     
    #6 Patrick Wong, Jun 30, 2013
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  7. Kurzweil

    Kurzweil Member

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    This happened to me and I had inadvertently shifted in into "B" (engine braking). Exactly what the OP said happened. However, he says that it has happened a few times which could possibly be a shift control problem? I would suggest checking the PRNDL display (the old term for auto-shift indicator) to see what "gear" the car is in. It should show "B" instead of "D" at the time the problem manifests, if we are on the correct track here.

    By the way, I thought the "Break Pedal" response deliberately obtuse. People mix those two words up all the time and most of us know the intent. Again, patience with new forum members. Or at least, let's be brilliantly funny about it! There's another word that gets substituted often on automotive forums but I forget that one.
     
    #7 Kurzweil, Jun 30, 2013
  8. XNak20

    XNak20 Junior Member

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    I've had it since 2005. I didn't touch my emergency brake, and I wasn't shifting into B when this happened, unless it did it by itself somehow. This only started happening in the past year, I used to just ignore it hoping the last time it happened would end up being the last time it would happen, but I want to get this thing figured out already.
     
    #8 XNak20, Jun 30, 2013
  9. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Next time this happens, pls look at your gear selector indicator to see if the transaxle is in D, or B.
     
    #9 Patrick Wong, Jun 30, 2013
  10. bisco

    bisco cookie crumbler

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    emergency brake can drag without you touching it, although, i think it would be all the time and more noticeable at slower speeds.
     
    #10 bisco, Jun 30, 2013
  11. northwichita

    northwichita .

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    Since there is an odd noise related to the 'braking' , I would also consider a wheel bearing going out, suggest to the OP looking at some of the threads concerning this.
     
    #11 northwichita, Jun 30, 2013
  12. XNak20

    XNak20 Junior Member

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    So it appears to be that my car was in B without me realizing it. I often drive with a GPS mounted on my dashboard and sometimes it falls off and hits the gear stick (I think that's what it's called?) and must've put it into B in the process. I was driving today and put it into B to see what happens and it made the same noise and did the same thing as what happened before, so that must be it. My question would be, would driving while in B do any long term damage to the car?
     
    #12 XNak20, Jun 30, 2013
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  13. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    No.
    You will have slightly poorer gas mileage during braking, but that is it.
     
    #13 JimboPalmer, Jun 30, 2013
  14. moshe1436

    moshe1436 Bought used.

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    Glad you found out what the problem was. Change the location of the GPS!! Now you can enjoy your Prius without worrying about the "problem!"
     
    #14 moshe1436, Jun 30, 2013
  15. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    If you can't engage cruise control, that is a symptom of being in B.
     
    #15 JimboPalmer, Jun 30, 2013
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