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Braking problem

Discussion in 'Gen 3 Prius Main Forum' started by eglmainz, Jun 22, 2009.

  1. The Electric Me

    The Electric Me Go Speed Go!

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    Re: Acceleration Surge Going Over Bump

    I stand corrected. You are right, I misread his original post. He is talking about a feeling "before" braking. So I apologize to the OP. This is a slightly different sensation then the "braking" problem that has been reported.

    I also am supremely careful or hesitant to accuse anyone of being a troll, having been accused myself. I honestly was simply warning the OP that he was in "danger of" that label being attached. But yes, my approach is to always assume the sincerity of a post and poster.

    Anyway, thanks for pointing out my mistake, and my bad.
     
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  2. hockeydad

    hockeydad New Member

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    Re: Acceleration Surge Going Over Bump


    Ah, yet ANOTHER 1 poster! Troll away, dude. But next time, try reading (all/most) of what i've posted on this subject. If there's ANYBODY here that cares most about gathering the facts, and separating out hype and spin, it's your's truely. But thanks for coming. :rolleyes:

    By the way, you lose all cred when you make a statement like this - "No one cares about your opinion". For two reasons: (1) You don't speak for everyone, so don't assume that you do, and (2) I seek facts, not opinions. If you had actually done your homework, Sgt Friday, you would know this, and I wouldn't have to explain it to a newbie like you. Dig it? :doh:
     
  3. qbee42

    qbee42 My other car is a boat

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    Re: Acceleration Surge Going Over Bump

    You missed a detail on the OP. The OP made no reference to braking, which is entirely a different issue than all of the "accelerated during braking" hysteria threads.

    Perhaps it was simply an oversight, and the OP really meant to say that he was braking when the "acceleration" occurred. I can't infer that without more information.

    If he really did mean that this was a braking situation, then, jeeze, that is pretty stupid. This site is *filled* with threads about that.

    Tom
     
  4. hockeydad

    hockeydad New Member

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    Re: Acceleration Surge Going Over Bump


    Tom,

    Clearly there is some confusion with many posters between the braking and acceleration issues. Might be useful if the moderators either combined all these threads, or re-directed new posts on this same subject. There are way too many threads to follow...

    To summarize my understanding of things:

    (1) Several Toyota models (does NOT include the Prius) have reported problems with acceleration. Causes have ranged from floor mats to sticky gas peddles. Some here would like to think that #2 (below) is somehow connected to this problem, but I do not believe that it is, nor have I seen any evidence to suggest that issues #1 and #2 are connected.

    (2) Some on here have reported a sudden, but sub-one second loss of braking when going over bumps. Some have characterized this as a "lurching" or "acceleration" issue. I have suggested (in a prior post) that this really is a sensation that is caused by this suden change in momentum. Further, i have expereinced this braking issue - once - myself. But have NOT expererienced it again since applying more braking pressure that i use to. This leads me to believe (at vleast in my case), that there is NO flaw or actual problems with the Prius brakes, but what I expereinced was a sensation that results because of the regenerative braking. G2 owners have reported the same thing, and no investigations have resulted. If it's a real problem going back years, then I would expect that some investigation would have resulted?
     
  5. qbee42

    qbee42 My other car is a boat

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    Re: Acceleration Surge Going Over Bump

    Right. This, however, is the first time I've heard anyone claim to have unintended acceleration over a bump while *not* braking.

    Personally, I think it is a poster or user error. I suspect it's either the braking over a bump thing, or simply blipping the accelerator pedal when going over a bump. I'll be amazed if it's really anything else.

    Tom
     
  6. hockeydad

    hockeydad New Member

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    Re: Acceleration Surge Going Over Bump


    Personally, I give no significance to only one incident of anything. IMO, there has to be some meaninful statistics behind an event before passing judgement on whether it's worth pursuing.
     
  7. Econ

    Econ Member

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    Re: Acceleration Surge Going Over Bump

    On my 2010, I did experience something with the braking while braking over some rail tracks. It took me by suprise but I did not feel any acceleration
     
  8. qbee42

    qbee42 My other car is a boat

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    Re: Acceleration Surge Going Over Bump

    This is common. If you are interested, there are a *lot* of posts about it on several other threads.

    Tom
     
  9. spinkao

    spinkao New Member

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    Re: Acceleration Surge Going Over Bump

    No need to apologize - I almost did the same thing and was about to answer "Oh Jeeez, another acceleration-under-braking guy!", but then I re-read his post again and noticed I was wrong :). There was also higher-than-usual concentration of trolls on PC recently, so I was also wary because of that, but this guy might have a real problem.

    Although I totally agree with Tom and also think that maybe he depressed the accelerator unintensionally when going over a bump. As far as I know, there were no problems of this kind reported yet and I am extremely cautious about any first-time report of such a weird problem. But you can never know for sure...
     
  10. spinkao

    spinkao New Member

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    Re: Acceleration Surge Going Over Bump

    As Tom says, this is a well-known issue, affecting all Prius generations. Personally, I think it's no big deal; it never really scared me, not even the first time, although it felt a bit weird. Now I am used to it and it poses no problem for me.

    I don't experience this phenomenon very often though, maybe because I am used to coast as much as possible and when I really have to brake, I prefer gentle, steady braking to slowly charge the battery and regenerate as much energy as I can. This only happened to me several times when I had to brake harder-than-usual and went over a manhole or something.
     
  11. GreenGuy33

    GreenGuy33 Active Member

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    Re: Acceleration Surge Going Over Bump

    Wow, I thought I was imagining that. I get the same, exact thing when I hit a bump and go to brake but find myself accelerating.
     
  12. hockeydad

    hockeydad New Member

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    Re: Acceleration Surge Going Over Bump

    I don't think it's normal, and has not happened to me.
     
  13. hockeydad

    hockeydad New Member

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    Re: Acceleration Surge Going Over Bump


    If I'm reading this right - You hit a bump, then begin to brake and find yourself accelerating. That's not what rboyd described. He said he hits a bump and then accelerates as if the cruise control kicks in. This phenomena then "caused him to hit the brakes" to bring the acceleration down. The sequence is different. I did not see where he said he's braking prior to accelerating. Not clear these are the same?
     
  14. timbobo3

    timbobo3 Junior Member

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    Just found this thread. I have an '07. Happens to me every day on one long downhill at 40 mph as I cross a bridge over a hydro-dam. I hit the expansion joints, go airborne for a moment and when I return the brakes "lose" braking ability and then regain it. Very strange and unnerving when cars are in front of me. Don't like it at all. I expect a recall for some firmware update someday. ABC news featured this last week amid the huge recall debacle (completely unrelated!).
     
  15. Chaz

    Chaz Junior Member

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    Yes, I would suspect some bulletin from them in the future too...I'd bet $20 on it ..lol
    Careful timbo, you only have 13 posts and hockeydad may be all over you for posting this as you are new ;). He supposedly is the expert on this issue, or a shill for Toyota.:D Bottom line I posted the behavior and said nothing bad about Toyota. I said I called dealer and said it was happening, anyone else experiencing problem...that's it. Not an urgent issue like the acceleration recall, but why not let them know along with nhsta. They are the experts so let them decide if it's "normal". If they come back and say that is the way these types of brakes currently work, so be it, but with so many people posting about on FB and here, drivers should be aware of the issue and they should post an advisory. According to hockeyguy, who actually had it happen !!! ;), we should all just learn how to drive like he does and keep quiet...LOL! "Don't worry about it, it will happen once and shock you, then just get used to it...lol. Also, if you only post once and are a newbie, we should be ignored.
     
  16. wvgasguy

    wvgasguy New Member

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    Re: Acceleration Surge Going Over Bump

    comment deleted
     
  17. PriusSport

    PriusSport senior member

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    Re: Acceleration Surge Going Over Bump

    There's that word "surge" again. LOL.

    That's the braking/stability system working. I had the stability light (just below the "ready" sign on the dash) flash on briefly when I went over a construction rough spot a few days ago. That may be a function of tire pressure. I had just pushed my tire pressures up to 40/38 psi, more than usual, which stiffened the ride some and caused slightly more bounce.

    Funny, these cars have been driven 6 years and millions of miles with the best reliability record in the industry--based on Consumer Reports' surveys. All it takes is some bad media, and people start seeing things.

    I want to add that I got caught out in a snowstorm yesterday afternoon. The first time, thanks to faulty weather reporting--the forecasters missed it. The Prius performed very well on main and secondary roads partly stuck with snow. That's with OE tires. I got up my hill in an inch or so of packed snow just fine. The roads had not been plowed or salted yet, since it was still snowing.
     
  18. ludovico

    ludovico New Member

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    Re: Acceleration Surge Going Over Bump


    I have had this problem with my 2010 Prius as well. For example, when I'm driving and I brake in anticipation of a bump in the road (such as a railway crossing) - when I do hit the bump with MY FOOT ON THE BRAKE the Prius lurches forward. It has been doing this since I got the car 3 months ago. I've called Toyota and they deny they've heard anything from anyone about such a problem - and suggest I not even bring it in for a look from the maintenance staff. I am very disappointed in this situation with car I otherwise like very much.
     
  19. bestmapman

    bestmapman 04, 07 ,08, 09, 10, 16, 21 Prime

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    Re: Acceleration Surge Going Over Bump

    The OP made quite the post. It is the equivalent of lighting a firecracker and throwing it into a crowded room and seeing what happens.

    :lol:
     
  20. hockeydad

    hockeydad New Member

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    Re: Acceleration Surge Going Over Bump


    In internet parlance, it's called "handgrenading". The die-hards will dive on the handgrenade (bad comment), while others will scramble to get away. My fovorite is dropping into an ESPN chat after a football or basketball game and watch someone make a negative comment. Even if that person doesn't believe what they posted themselves....watch what happens. :eek: It can be quite entertaining if you happen to be a troll. :rockon:
     
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