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Lost mpg after having Hybrid battery replaced

Discussion in 'Gen 2 Prius Fuel Economy' started by Llamas07, Dec 17, 2019.

  1. Llamas07

    Llamas07 New Member

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    I just had a hybrid battery replaced a week ago and I have lost 10mpg since. They are telling me the cause is possibly a dirty throttle body. I'm just wondering if anybody has had similar situation or any other advice.
     
  2. Aaron Vitolins

    Aaron Vitolins Senior Member

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    What is your current mpg? And how many miles on the car?
     
  3. dolj

    dolj Senior Member

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    With what? OEM new or a "rebuilt" of second-hand old modules?
    So, they reckon the throttle body mysteriously gunked up at the exact same time they replace the HV battery?

    In any case, you will need to run three or four tanks of gas and then average the MPG over them to get a better idea of your current MPG. Ideally, you should have been recording your MPG per tank for some months before you had the battery swapped, otherwise, you don't really know what average MPG you were doing.
     
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  4. George W

    George W Senior Member

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    first thing suspected is the last thing changed. Have you used code readers/smart apps before?
     
  5. dubit

    dubit Senior Member

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    It's getting cold... MPG's for me are down as well & to be honest, that's the first thing I'd suspect as the culprit. So like dolj mentions up there average this out after a 5 or so fill-ups and see. Secondly, and you may laugh at this, but check your tire pressure. That's a big mpg reducer & the person who did the work on your vehicle may have adjusted the pressure.

    Also just curious. Is this a "rebuilt" battery or new from a Toyota dealer? There are literally hundreds of threads here regarding those rebuilt batteries. Very, very few are complimentary. :(
     
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  6. bisco

    bisco cookie crumbler

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    welcome to priuschat!