Prius runs fine when (cold), but low MPG and engine stays on when hot (MarieAnie's thread)

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by MarieAnie, May 5, 2019.

  1. MarieAnie

    MarieAnie New Member

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    #help me
    Hello, I'm new here and I hope you will help me, you're my last hope, because I have already tried everything. It's aready quite hot in my country now. So, as I said, engine running all the time. Low 28MPG. Today I changed battery, 7 of them where dead. Tech cached the car on compiuter and there weren't any error or thomething like that. They also changed vent of battery, but there no any reasult. After the car gets hot, MPG is getting low and low and low and the engine works only on the fuel, not on battery. When I tund off the engine and the car gets cooler, it starts working on the battery, but after getting hot the car, it works only fuel again.
    What ealse can be? Compiuter diagnostic shows nothing. Please, any help
     
  2. bisco

    bisco cookie crumbler

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    you need a new battery, how many miles on her?
     
  3. MarieAnie

    MarieAnie New Member

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    I chaked them, 7 was dead and changed, I also changed vent system.
     
  4. landspeed

    landspeed Active Member

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    MarieAnie - is the car itself actually overheating? Does it have any warning lights?
     
  5. MarieAnie

    MarieAnie New Member

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    Yeah, by itself, when I'm driving and car is cool it warks good, no any warning lights, and when it's getting hot, doesn't work on battery any more, only running fuel engine low mpg 28_30.
     
  6. bisco

    bisco cookie crumbler

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    changing cells doesn't work, you need a new battery, or at the very least, a complete balance procedure
     
  7. bisco

    bisco cookie crumbler

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    i suspect her battery is overheating, and self protecting limiting of output.
     
  8. landspeed

    landspeed Active Member

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    I strongly suspect this too - it would be awesome if the problem was that the battery fan wasn't spinning and that was the cause of the problem, as the car could be saved quite easily!

    (I assumed Gen 2 but it could be Gen 1. I hope it isn't Gen 3 otherwise we need to consider the fact that the (E G,r) I think, gets blocked, and destroys the he G). I have deliberately obfuscated those terms because they would induce fear in most car owners! Hopefully it is a Gen 2 :)
     
  9. landspeed

    landspeed Active Member

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    To MarieAnie (and others where applicable):
    When you say the problem is only when hot, can I ask:
    -> Is the problem only when the weather is hot outside?
    -> Or do you mean, the problem only happens when the car has been driven for a few minutes?

    Also - where do you stay? Are you in the USA, Georgia, or somewhere else?

    Also, what year is your car made? It is somewhere between 1999 and onwards, probably 2001 or later...
     
  10. Raytheeagle

    Raytheeagle Senior Member

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    There should be warning lights for these conditions. Is the dash working, as in is the combo meter up and running?
     
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  11. SFO

    SFO Senior Member

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    Seems odd that we have no 'codes'. Might try a new "tech", or buy a $1 USD OBD2 bluetooth adapter and the appropriate App.

    Given the problem (read the thread) and the steps taken (HV battery / HV fan), it sounds like a failed inverter pump or trapped air :whistle:

    There should be some DTCs logged, somewhere.. or not :cautious:
     
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