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Variable speed limit for EV mode?

Discussion in 'Gen 3 Prius Technical Discussion' started by shaun5stu, Apr 29, 2010.

  1. shaun5stu

    shaun5stu Junior Member

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    Does EV mode have a variable speed limit as to when it disengages? Most time I can get to 25 MPH in EV mode (and that seems to be the consensus from what I've read here). However, occasionally, at 10 MPH, the car will drop out of EV mode and I'll get the "excessive speed" warning. From what I can tell, this is not related to engine temperature, as it just happened to me again today returning from lunch. The weather is warm and I just drove about 2 miles, so the engine was warm also.
     
  2. GrumpyCabbie

    GrumpyCabbie Senior Member

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    It depends on many many factors, including various temperature limits such as outside temperature but also the battery temperature. They can be too hot or too cold.

    I believe this is to protect the battery. It is a tease having EV mode but it is fun whilst it works.
     
  3. Aegison

    Aegison Member

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    I know we can't change it, so I'm tilting at windmills, but I think Toyota really missed the boat on their logic for accessing the EV mode. From time to time, I have to drive (sorry, can't walk or bike it) less than a half mile and then stay there for a time. Then back I come.

    Well, when I leave home, the ICE starts its warm-up cycle, which isn't complete when I reach my destination. Then, the ICE etc. all cool off and will need a new warm-up cycle when I head for home.

    I think I should be able to use EV mode in going there so as to avoid a warm-up cycle which is inefficient - and to avoid it especially since the car will be shut off before it's even fully warmed up if it's cool out ... and it will in any case need a warm-up cycle on the return trip.

    Then, I can drive back and let the computer use/charge the battery and ICE as needed, and go through just one unnecessary warm-up cycle. To me, that would be a truly positive feature -- avoiding an incomplete and wasteful ICE warm-up cycle.

    It would trade two useless ICE warm-up cycles for just one.

    Another thing I run into is that sometimes I have to park at the curb when I come home ... and there may or may not be a space very close by. When it's time to pull it into the garage, that's the perfect time for EV, as no warm-up is needed. But, we don't have that choice.
     
  4. RobertCh

    RobertCh Junior Member

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    I completely agree with Aegison. Before I got mine, I had thought (assumed) that it would be able to do something like that. Especially for very short & slow trips like moving from one parking spot to another nearby parking spot.
     
  5. GrumpyCabbie

    GrumpyCabbie Senior Member

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    I think the US version (or maybe just the Cal & a few other states) is different due to emission laws as I know on mine I am able to use EV straight away, even when cold, so long as I press the EV button before the engine fires up.
     
  6. ItsNotAboutTheMoney

    ItsNotAboutTheMoney EditProfOptInfoCustomUser Title

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    It depends on what "stage" it's in. You can find other threads that explain the warm-up stages.

    Three different possibilities:
    - too cold: can't go to EV
    - a bit warmer: can EV to 10mph
    - warmed up: can EV to 25mph.

    Of course it will run on battery only at higher speeds, it's just the EV mode that drops out.

    As Grumpy mentioned it's different in the EU. The restrictions are due to the stricter US emissions laws.
     
  7. 808mom

    808mom New Member

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    I just got mine on Saturday, and noticed that when in EV mode, if I accelerate too quickly (even while under 25mph) I get kicked out of EV mode. Since this is my first hybrid, it's taking a while to get adjusted to how differently the acceleration is (I was driving a 6cyl camry before this so it's quite a change!). Love it so far though!
     
  8. GrumpyCabbie

    GrumpyCabbie Senior Member

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    Acceleration is not quick in EV mode. Try to keep below the red power band in EV and you should be able to keep in EV longer. It is only useful for fun as it will seriously eat your battery charge and that will adversely affect your mpg - the engine is used to put that charge back in.

    Still good fun and you'll slowly get used to how it works. I still love mine, even after 10 hours a day, 6 days a week.