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why is there regen with your foot off the gas?

Discussion in 'Gen 2 Prius Fuel Economy' started by geologyrox, Jan 2, 2006.

  1. geologyrox

    geologyrox New Member

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    i admit i don't own a Prius, i've only got about 400 miles behind the wheel of one to my name. Luckily, though I hadn't done any intensive reading, I'd heard enough about feathering and the no-arrows condition to average 54.8 mpg for the whole trip.

    I've been wondering, though, why Toyota wouldn't want to design the Prius to NOT regen with the foot off the gas - if the no-load condition is the most efficient (which seems to be the overriding opinion) wouldn't it make sense to make that be the default no gas / no brake setting? It seems that the manufacturer made the choice to have regen occur, instead of coasting. Why would they have done this? I'm honestly confused - it really doesn't seem sensible. Anyone have a little insight?
     
    #1 geologyrox, Jan 2, 2006
  2. 8AA

    8AA Active Member

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    My understanding is that Toyota wanted to simulate the engine drag experienced with most conventional gas powered cars. For a similar reason, if you're stopped, when you take your foot off the brake the car creeps forward. This programming was meant to simulate an idling conventional car with an automatic transmission.

    Others have commented that having your foot off the gas should let the car glide instead of coast, but after a while it becomes second nature to feather the gas pedal. I would rather let the car coast up to a stop than trying to feather the brake without engaging the hydraulic brakes.
     
    #2 8AA, Jan 2, 2006
  3. Bill Merchant

    Bill Merchant absit invidia

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    8AA's right, Toyota wanted to make the Prius as "normal" as possible for most drivers, so they simulate automatic transmission drag and creep.

    I just wish they would have a counterpart to the cruise control, maybe Glide Control that would turn off the simulation and let you set a smart cruising speed.
     
    #3 Bill Merchant, Jan 2, 2006
  4. banksmi1

    banksmi1 New Member

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    In that mindset is it really harder on the transmission if you shift the car into neutral rather then fiddling with the feathering? I just got my 2006 3 days ago and am wondering which I should start to utilize?

    Thanks
    Mike
    2006 Black Option 4
    265 miles @ 43.7 MPG
     
    #4 banksmi1, Jan 5, 2006
  5. geologyrox

    geologyrox New Member

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    Mike, I was in your boat completely - I assumed I'd use the neutral because i'm so used to it now, with my current car. after a short while in the prius, feathering became second nature, and I feel safer - I can respond fully in one step instead of two to any situation that might come up, and I'm still using no gas. Give yourself a little practice before yougive up on feathering.

    And it still disappoints me that with so much of this car tuned into software and electronics, that there aren't a number of different options accessible on the MFD that allow you to customize things like the cruise control - or at least traditional/economical settings that use two or three different set 'modes' to optimize the car for different reasons
     
    #5 geologyrox, Jan 5, 2006
  6. Tideland Prius

    Tideland Prius Moderator of the North
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    Well, neutral's just the easy way out. The difference is that with feathering, you're still in D and thus if anything should occur you can accelerate out of it. Also, feathering will become second nature as you feel when the motors stop resisting and you glide.
     
    #6 Tideland Prius, Jan 5, 2006
  7. banksmi1

    banksmi1 New Member

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    Thanks. I had to drive on the freeway today to go a plant for work and in rush hour traffic I was able to practice the feathering a little bit and averaged over 65mpg for a 40 mile trip. Even had a single 5 minute slot of over 80 (One day I will get that 100mpg for 5 minutes...) Best so far.

    Since the car still only has 300 miles on it I wanted to keep the speed under 60, thank goodness for traffic, I was really starting to tick my gas guzzling peers off not flying down at 80mph. I will work on the feathering a lot more, the first 250 miles I was using solely cruise control and neutral.

    Thanks again
    Mike
     
    #7 banksmi1, Jan 6, 2006
  8. Tideland Prius

    Tideland Prius Moderator of the North
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    That's good! Keep it up!
     
    #8 Tideland Prius, Jan 6, 2006
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