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Glide degenerating slowly and slowly

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by SWprius08, Sep 17, 2014.

  1. SWprius08

    SWprius08 SoCalprius

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    I remember when my 08 prius (std) was fairly new, the glide used to be very free, now with about 90K miles it seems like the glide is getting lesser and lesser free. Seems like something needs to be lubrication. This started with my old set of worn tires and continuing with a new set, I have already eliminated the possibility of this being caused by tires or tire pressure. I have noticed a drop in fuel economy as well and am sure it is because of this drag that has emerged from somewhere causing the engine to turn on more often. Any one else has experienced the same issue? is this a known issue with a known fix? I have done regular oil change and done few major services at the dealership. Any helpful input will be appreciated.
     
  2. Eclipse1701d

    Eclipse1701d Prius Enthusiast

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    One simple thing would be to check if your wheels spin freely. Raise each corner of the vehicle with a floor jack (of course, using the designated area under the vehicle) and see if the wheels spin freely. You could have a front brake pad slightly touching the disc, or need an adjustment to your rear brakes or e-brake in the rear. Another thing could be a wheel bearing that has worn and causes more drag, which would also show up during the spin test. I have never had to do this, but I think you may have to have the car in neutral to check the front tires for spin (to disengage what would be the parking pin on a normal transmission). If so, please put a piece of wood or other object behind the rear tires to prevent the car from moving and injuring you or someone else!
     
  3. SWprius08

    SWprius08 SoCalprius

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    Thank you for reply, I should have mentioned this but yes I had ruled out that possibility as well. The tires are very free in neutral, they are more free in neutral than in glide, in one of the articles from a experienced hypermiler he mentions that "during glide very small, practically negligible current comes out of the battery pack to keep the car rolling a little easier than if you were in neutral", this is reverse in my Prius's case. After doing some more research I am forced to think that either the Transaxle oil needs to be flushed and/or fuel injection system needs to be cleaned. Considering I am about 90K which is only 10K less than 100K and I understand these services are recommended at 100K.

    So it turns out that this is certainly not a known issue with a known solution. Hence more discussion is needed!
     
  4. Sabby

    Sabby Active Member

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    First thing I would check is to make sure the wheels are free wheeling and that one of your brakes is not causing the drag. I assume your wheel bearings are quiet and are not causing any problems. Another item that could cause the drag is an alignment problem.
     
  5. SWprius08

    SWprius08 SoCalprius

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    No noise from wheels, wheels are free in neutral, alignment done 2000 miles ago with new tires. I can completely conclude from the sound of the engine that is working hard to push the car in the initial pickup and then when try to glide it would not glide as much as it used to on the same exact road.
     
  6. bisco

    bisco cookie crumbler

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    it sounds like, as your battery is slowly wearing out, the car is trying to regen more, without success. have you tried gliding in neutral?
     
  7. SWprius08

    SWprius08 SoCalprius

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    Yes gliding in neutral is more free then gliding in drive. I dont quiet think it is the battery, (although I could be wrong) becausee even when the battery is green and all charged up the pickup seems to drag a little making the engine work a little more hard, i could hear the sound of engine, this would even happen after a glide moment when i go for the pulse
     
    #7 SWprius08, Sep 18, 2014
    Last edited: Sep 18, 2014
  8. SWprius08

    SWprius08 SoCalprius

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    Since the engine is working more harder i feel somewhere between the engines and wheels there is this unnecessary friction present.
     
  9. valde3

    valde3 Senior Member

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    You do remember that when gliding in Prius you have to press little bit gas pedal so that no arrows point into or out of the battery on the "Energy" display? If it actually coasts more freely in neutral than in drive then there has to be some electronic problem since there is no real difference between the two.

    Rear alignment can be pretty bad and still be within specs. Shop won’t adjust it case it can only be adjusted by using shims (witch Toyota doesn’t recommend) or by replacing rear axle.
     
    #9 valde3, Sep 18, 2014
    Last edited: Sep 18, 2014
    SWprius08 likes this.
  10. bisco

    bisco cookie crumbler

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    if the engine is working harder with the battery fully charged, that makes me suspect the battery even more. you're seeing a display of a mathematical calculation of battery charge, but it is not telling you the health of the battery. but you could be right, maybe your transaxle is going out.