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Jolt when taking off from dead stop

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by dcwenger, May 3, 2024.

  1. dcwenger

    dcwenger Junior Member

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    So I just bought this 2008 Base model last week. The person was getting rid of it because she bought it in January of this year, not knowing it had a whole host of issues and didn’t want to put any money into it. It needed a cat and a hybrid battery. I have both on my ’07, which has seen better days, so I bought it from her for $1800. My dad and I took my newly refreshed battery from my ’07 with us to San Diego and after purchasing the car, swapped out the battery. It drove beautifully home (80 miles at 65-70 mph) and got about 45 mpg. It was really smooth, but then I noticed from a start at a traffic light or stop sign, there was a bit of a jolt while taking off. It is also noticeable when starting the car and turning it off. I changed the lower engine mount (swapped from my ’07), but that didn’t change anything and there still seems to be significant movement in the engine. This is my 5th Prius. I have an ’07 with 320,000 miles, a ’13 Persona with 110,000 miles, an ’05 with 377,000 miles and another ’07 I bought for my dad with 150,000 miles. None of them have ever had this issue. This car only has 201,000 miles on it. Just for giggles, I took it to Firestone this morning to have them do an inspection on it. I thought for $9.99, they could tell me what was wrong and then I could go from there. They were all over the place with their diagnosis and kept changing what they said was the issue (they had no clue). The mechanic said I need the right and left engine mounts and also said I need struts in the front. I didn’t detect any issues with the ride like I have on my others when they needed struts, so not sure that would be the issue. Also, if the struts were the issue, it wouldn’t be noticeable while the car is sitting in the garage. I want to fix it and don’t mind putting the money into it, but I don’t want to waste time chasing a problem and not finding the issue. I plan to give this to my daughter in AZ (which means I can leave the aftermarket cat on there and keep my two extra CARB compliant ones for the next projects), but I want to make sure it is headache free for her. I am thinking it is a possibility that it is a bad CV, but not 100% sure. Any assistance would be greatly appreciated
     
  2. bisco

    bisco cookie crumbler

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    does the jolt come before the engine starts?
     
  3. dcwenger

    dcwenger Junior Member

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    No. It comes right when the ICE kicks in. and when it is turned off.
     
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  4. dolj

    dolj Senior Member

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    I have noticed that a rough transition to/from electric or on stopping usually goes away after I recondition the hybrid battery. I don't recollect a rough start when the engine kicks in, though.
     
  5. bisco

    bisco cookie crumbler

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    I wonder about the clutch’
     
  6. BiomedO1

    BiomedO1 Senior Member

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    Check the flex plate, that connects the engine to the transmission. May be cracked / broken springs, so when things transition, you get the hurky-jerky.

    Good Luck...
     
  7. dcwenger

    dcwenger Junior Member

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    Thank you. How do I check the flex plate?
     
  8. BiomedO1

    BiomedO1 Senior Member

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    There's usually an access and/or inspection window at the base of the bell housing. Usually held in place by two 10mm screws. I'm pretty sure it exist in your model.
     
  9. dcwenger

    dcwenger Junior Member

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    So I took it to my mechanic today and he confirmed the issue is the right (passenger side) engine mount. Said it is $875 including diagnosis, parts and labor (2.5 hours). How difficult is this one to change? I might just pay it and get it done unless I can do it myself with minimal cussing.
     
  10. dcwenger

    dcwenger Junior Member

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    Nevermind. I just found this video (
    )
    and there is no way I'm attempting that. 2.5 hours would turn out to be about 6 and I would probably never get it lined up or back together properly. I don’t like wasting money and can do a lot of mechanical work myself, but this looks like more of a hassle than it's worth.
     
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  11. dcwenger

    dcwenger Junior Member

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    Well it turns out, the problem still exists. The shop suggested that I change the lower engine mount (the dogbone), as he thinks that may be the issue. I think he's wrong because even though it was very old, I pulled it off my '07 that has been sitting in the driveway for 2 years before taking it to the mechanic. He said he could tell it was used, but the '07 starts and did not have this jerk when starting and stopping the engine or when taking off. Althgough he claims the engine mount was collapsed, that was apprently not the issue. He also said it might not hurt to change the trasnsmission mount, but he said that was probably not the issue. If anyone knows of a good hybrid mech here in SoCal (prefereably Inland Empire), please let me know. I hate it when I throw money down the drain due to guesswork and the problem still exists. This was nearly $1000.
     
  12. bisco

    bisco cookie crumbler

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    try hybrid pit
     
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  13. dcwenger

    dcwenger Junior Member

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    Thank you. I took it to another mechanic. He didn't check it out, but said it didn't make sense to change the engine mount, as that wouldn't change the symptom I described. He said it sounds like the clutch for the transmission, whch is an 8-10 hour job. That's going to be a big chunk of change.
     
  14. bisco

    bisco cookie crumbler

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    agreed. maybe time to retire it?
     
  15. dcwenger

    dcwenger Junior Member

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    Yeah. Not sure. Other than the shudder, it seems to run smoothly and gets great mileage. It might be a good car if that one issue is fixed, but not sure it's worth the money. If it lasts quite a while after that, it will be worth it, but not sure. It only has 201,000 on the car itself. The mechaninc who did the engine mount said it looks like the engine has been out, so not even sure if it's original (could have less miles). I'm going to take it by the dealer today and see if I can get an opinion on it.
     
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  16. pasadena_commut

    pasadena_commut Senior Member

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    Maybe see this thread:

    Clutch damper failure? Engine cutting out | PriusChat

    For tough problems I take Toyotas and Hondas to Fuji Auto in Pasadena. Reasonable prices and very competent. You will need an appointment though, if you just drop in the odds that they can squeeze you in are pretty low. Maybe call them and see what they think? They will probably be willing to give an estimate to replace the damper without seeing the car.

    Also, my 2007 gives a little jolt when the motor stops or starts and the car is not moving. Never felt anything when the motor turned on or off while the car was moving. Been like that since I bought it, and it hasn't gotten either better or worse in five years.
     
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  17. ChapmanF

    ChapmanF Senior Member

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    If there's a handhole in the blanking plate from the engine bottom to the bellhousing, as #8 suggested, you might reach down in there and feel around for any fragments of the damper's original coil springs. Sometimes when it's been severely beaten up, there will be some.

    Also, when that damper gets beaten up, there's probably a reason, such as a misfiring engine.
     
  18. dcwenger

    dcwenger Junior Member

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    Thank you. I'm in the IE (Canyon Lake), but it might be worth a drive to Pasadena if they are honest and reasonable.

    Yeah. Other than that, it drives fairly smoothly and is currently getting 47-48 mpg (according to the MFD readout). I've had others say it might not be a bog deal, but since I'm used to my other ones not doing that, it annoys me.
     
  19. dcwenger

    dcwenger Junior Member

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    Okay. I'll check for that. I don't notice a misfire, but I have a feeling whomever owned it before the person from whom I bought it really beat the crap out of it and abused it. I'm not sure how that's possible though because nether my 2005 with 378,000 or my 2007 with 320,000 have had this issue and I don't exacty baby them.
     
  20. dcwenger

    dcwenger Junior Member

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    BTW. The gentleman at Temecula Valley Toyota Service Dept. said he agreed it sounded like that was the issue. He said it doesn't happen that often with these, but he sees them once in a while. He said he would either sell it or just not worry about it, as the labor is nearly 15 hours and would cost me between $8K and $9K. He said the engine needs to come out. Obviously I'm not going to do that. I might pull the one off my '07 and put it on there, but I don't want to open a can of worms.