1. Attachments are working again! Check out this thread for more details and to report any other bugs.

216k, original hybrid battery...what would you do?

Discussion in 'Gen 2 Prius Main Forum' started by ukiltmybrutha, Aug 19, 2021.

  1. ukiltmybrutha

    ukiltmybrutha Member

    Joined:
    Nov 4, 2019
    139
    22
    0
    Location:
    VA
    Vehicle:
    2005 Prius
    Model:
    Touring
    Just wondering what steps you would take at this point. The battery appears to function correctly. Not impressed with fuel economy though. The car is short tripped about 7 miles in each direction and it is a real chore to average above 35 mpg....suspect the batteries while others seem to say that 35mpg for such a short trip is normal.

    Thanks.
     
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    trade for a corolla, but that might only get 20
     
    ukiltmybrutha likes this.
  3. ukiltmybrutha

    ukiltmybrutha Member

    Joined:
    Nov 4, 2019
    139
    22
    0
    Location:
    VA
    Vehicle:
    2005 Prius
    Model:
    Touring
    Serious or not? Funny you put it this way. I kinda feel like I would get 35mpg on a Corolla on that same trip.

    Dreaming?
     
    bisco likes this.
  4. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,448
    3,751
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    Personally, I think you should be getting 42-45 MPG so it might be worth looking a bit more into it.

    What is the general terrain you're driving? Is it hilly or flat?

    At 3.3 mi the engine should be warmed up enough to get to stage 4, so the remaining 3.6 mi should be getting pretty economic driving to balance the higher consumption in the first 3.3 mi.

    It could be your battery, have you thought about some reconditioning charge/discharge cycles?

    Wheels/bearings - have you check they rotate freely without brake/bearing drag?
     
    #4 dolj, Aug 20, 2021
    Last edited: Aug 20, 2021
    ukiltmybrutha likes this.
  5. Another

    Another Senior Member

    Joined:
    Jun 22, 2021
    1,802
    508
    0
    Location:
    Naples, Florida
    Vehicle:
    2007 Prius
    Model:
    Touring
    When were the plugs last changed? Also, has mileage dropped recently or has it always been in current range? In your area of VA is the terrain all hills?
     
    ukiltmybrutha likes this.
  6. TMR-JWAP

    TMR-JWAP Senior Member

    Joined:
    Aug 12, 2016
    6,058
    5,783
    0
    Location:
    Columbia, SC
    Vehicle:
    2007 Prius
    Model:
    Touring
    After having driven 7 or so different Gen 2s, I can confidently say (for a cold start) the first 5 minute interval on the MFD is almost always ~23-28mpg. That alone is going to make it challenging to have a high average if only doing 7 mile trips.

    There are several things that could be verified just to ensure they're not dragging you down, though. Even a weak/failing 12v battery can hurt MPG noticeably.
     
    ukiltmybrutha likes this.
  7. ukiltmybrutha

    ukiltmybrutha Member

    Joined:
    Nov 4, 2019
    139
    22
    0
    Location:
    VA
    Vehicle:
    2005 Prius
    Model:
    Touring


    I think that I should already know this but what do you mean about recharge/discharge cycles?

    I will check the wheel bearings.

    I have only had it for about 4k miles. I live in a pretty flat area. Previous owner seemed aggravated that he never got more than 40mpg....I assume even on longer trips.

    He provided all dealer service records and was very obsessive about dealer maintenance.

    I will check the plugs.
     
  8. ukiltmybrutha

    ukiltmybrutha Member

    Joined:
    Nov 4, 2019
    139
    22
    0
    Location:
    VA
    Vehicle:
    2005 Prius
    Model:
    Touring
    Missed this post.
     
  9. ukiltmybrutha

    ukiltmybrutha Member

    Joined:
    Nov 4, 2019
    139
    22
    0
    Location:
    VA
    Vehicle:
    2005 Prius
    Model:
    Touring
    Please expand on the reconditioning recharge/discharge cycles....it seems like this is a topic where there might be too much info. I would like to get the basic idea without getting into the weeds.
     
  10. mr_guy_mann

    mr_guy_mann Senior Member

    Joined:
    Sep 3, 2020
    3,206
    1,339
    0
    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
    The basic idea is to gently discharge and charge the battery modules at increasing limits that are well beyond normal use. Doing this can improve battery function, at least in the short term (no way around that fact that the battery is old and will fail much sooner than a new one).
    One way to do this is to use hobby or RC chargers to cycle each module individually. Pros: you can evaluate and test each module by it self, can cost less. Cons: takes lots of time- maybe six hours for 1 cycle times 3-6 cycles per module times at least 28 modules. More chargers speed this up but cost more.
    Second is grid charging- using a high voltage charger and discharger that can cycle the whole pack at once. Pros: less time needed. Cons: costs more, can't evaluate single modules.

    Posted via the PriusChat mobile app.
     
    #10 mr_guy_mann, Aug 20, 2021
    Last edited: Aug 20, 2021
    ukiltmybrutha likes this.
  11. ukiltmybrutha

    ukiltmybrutha Member

    Joined:
    Nov 4, 2019
    139
    22
    0
    Location:
    VA
    Vehicle:
    2005 Prius
    Model:
    Touring
    Thank you for laying this out.
     
  12. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    serious, but guessing at mpg's. all cars suffer during the warm up cycles and pollute the most then.

    have you considered recording full tank mpg's and averaging them?

    dr. prius app can help you with battery health if you're technically inclined
     
    ukiltmybrutha likes this.
  13. Colorado Boo

    Colorado Boo Active Member

    Joined:
    Jun 23, 2021
    307
    201
    8
    Location:
    Monument, Colorado USA
    Vehicle:
    2021 Prius
    Model:
    LE AWD-e
    Lots of things can impact mileage, including dirty fuel injectors. Run a small bottle of Lucas Oil fuel injector cleaner in the gas tank. Check/clean throttle body and MAS sensor. About once a month or so, do an Italian tuneup on that engine.
     
  14. ukiltmybrutha

    ukiltmybrutha Member

    Joined:
    Nov 4, 2019
    139
    22
    0
    Location:
    VA
    Vehicle:
    2005 Prius
    Model:
    Touring
    Thanks.

    I think I will go with the doctor Prius app at first. I might go with the lithium batteries but that seems wasteful for such short trips.

    I am up on the fence.

    What is it like when the battery as a whole effectively gives up the ghost? Is this the sort of thing that will leave my wife and kids stranded in the middle of the road?

    This car really is her beater car. She is not technically inclined or mechanically inclined whereas I am both....just bored with working on cars at times.
     
  15. douglasjre

    douglasjre Senior Member

    Joined:
    Sep 13, 2008
    1,743
    613
    0
    Location:
    Orlando, FL
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    If there's new service lights I'd keep driving it and be grateful to still runs. If there are service lights I put it on techstream. Slow EGR flow can hurt fuel economy. But if it's not coming up as a pending code then it's not slow flow so don't go cleaning the EGR if you don't have to. Worn piston rings and low compression can hurt feel economy. Why chase it. Just be grateful it works
     
  16. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,448
    3,751
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    Where exactly would one find the EGR on a Gen 2? :p;):D(n):whistle:

    Putting it on Techstream if there are lights is a good idea though.
     
  17. ukiltmybrutha

    ukiltmybrutha Member

    Joined:
    Nov 4, 2019
    139
    22
    0
    Location:
    VA
    Vehicle:
    2005 Prius
    Model:
    Touring
    No lights and thanks for the advice.

    Still have the below question:

    What is it like when the battery as a whole effectively gives up the ghost? Is this the sort of thing that will leave my wife and kids stranded in the middle of the road?
     
  18. mr_guy_mann

    mr_guy_mann Senior Member

    Joined:
    Sep 3, 2020
    3,206
    1,339
    0
    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
    It depends on how it fails. The most common way is when one or more modules deteriorate and lose capacity. The "battery gauge" on the MFD shows rapid change from 6-7 bars down to 1-2 and then back up again. MPGs drop by 10-15. Reduction in accel (and louder ICE operation) as the battery "runs low on juice". Eventually the ecu sets codes and the warning lights come- but it USUALLY takes a bit before it disables the car.

    There are some failure modes that can prevent the car from starting or moving, that might not give much warning.

    Posted via the PriusChat mobile app.
     
    #18 mr_guy_mann, Sep 3, 2021
    Last edited: Sep 3, 2021
  19. ukiltmybrutha

    ukiltmybrutha Member

    Joined:
    Nov 4, 2019
    139
    22
    0
    Location:
    VA
    Vehicle:
    2005 Prius
    Model:
    Touring
    We decided that we are going to run the risk. Do you think something like a prolong charger might be beneficial? There are some incredibly long threads about that. Also, do you know if the prolong charger can work for future batteries like the Nexell Lithium packs?

    I know that you provided an easy on the eyes read on the basic idea which had me thinking about something like the prolong.

    I could always email the prolong folks but curious. If those lithium packs drop in price the prolong could begin to pay for itself.

    I guess what might be a disturbing find would be finding a bad cell or something like that. Kind of a cyclic waste of time and money now that I think about it more.

    Thanks.
     
    #19 ukiltmybrutha, Sep 3, 2021
    Last edited: Sep 3, 2021
  20. drone13

    drone13 Active Member

    Joined:
    Dec 5, 2020
    140
    115
    0
    Location:
    SoCal
    Vehicle:
    2008 Prius
    Model:
    Two
    The first thing I would do is fill the tank, zero the trip odometer and reset the fuel consumption on the MFD and then drive for 1 to 2 hrs. and see what normal long trip fuel economy shows. This will take the short trip economy out of the picture for this. After you have the baseline for a long trip cycle you will have a better idea of the actual state of the car. Let us know the results.

    If using A/C you can expect a decrease in economy. On my 07 this works out to 3 to 4 mpg, which seems to be quite normal.

    Other things to consider is components like brake dragging, wheel bearings, tire pressures, engine condition, etc. The Prius is a very low drag vehicle and anything that increases drag or affects engine performance can reduce mileage. Sometimes the reduction can be significant. As others have mentioned, the engines running condition can have a large effect on mileage if not running well.

    When I changed my tired old HV battery to a brand new pack the mileage didn't change. With A/C on auto (generally hi fan to medium fan) I'm getting 48mpg. Without A/C I'm getting 51 to 52. The old pack was getting the same fuel economy. I never got HV battery codes before I put in new the new HV battery, but the pack was obviously getting tired. The vehicle had 130K when I changed the pack. I think the battery would need to be bad enough to start throwing codes before you are likely to see that have a major effect. But that's only judging from my experience.

    Try doing the long drive baseline and let us know how that goes. I'm assuming you have had no check engine or RTODs since that wasn't mentioned. And yes... definitely get the Dr Prius app (with the paid upgrade so you can do a lifecycle test). Since you'll have the OBDII BT adapter also get the Torque app or Hybrid Assistant depending on whether you use Android or IOS for much greater detail on all the vehicles systems.

    Good luck