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Does neutral ruin the CVT?

Discussion in 'Gen 2 Prius Fuel Economy' started by Dolce_Vita, Feb 18, 2011.

  1. Dolce_Vita

    Dolce_Vita Member

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    Hi :)

    My commute has recently change to just 3km (1.8miles), and the weather is getting cooler now that summer has almost ended, so by the time my warm up cycle has ended i've basically arrived at school or arrived home.

    The roads are pretty rough as it's semi-rural and suburban, so getting a glide is pretty hard and the warm up cycle makes it even harder.

    Will using neutral to glide damage anything? The speeds are no higher than 43mph, so i wouldn't imagine i'd be putting too much strain on MG1?

    Thanks :)
     
    #1 Dolce_Vita, Feb 18, 2011
  2. pEEf

    pEEf Engineer - EV nut

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    No damage, you can shift into/out of neutral anytime. Be warned that you will get no battery charging in neutral though!

    Save for crashing into something, the Prius is smart enough to protect itself from the driver. Even if you press park while driving it will not do any damage (it will go into neutral).
     
    #2 pEEf, Feb 18, 2011
  3. Dolce_Vita

    Dolce_Vita Member

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    So pressing park while driving is pretty much a quicker way of putting it in neutral?

    What happens if you put it into reverse at speed? (out of interest)
     
    #3 Dolce_Vita, Feb 18, 2011
  4. ItsNotAboutTheMoney

    ItsNotAboutTheMoney EditProfOptInfoCustomUser Title

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    I think that it might also go into neutral. It does at low speed. That makes it handy for emergency neutrals.
     
    #4 ItsNotAboutTheMoney, Feb 18, 2011
  5. fuzzy1

    fuzzy1 Senior Member

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    INATM is right, Reverse at speed also goes to Neutral. Instantly, and with a double beep warning, at any speed above parking lot speed. Lacking a clutch, this is my emergency path out of gear.

    The theoretical risk we know about is of overspeeding MG1. If you start rolling down a hill with the ICE off, at some higher speed (varies by generation) it will start up to protect MG1. But when in Neutral, the ICE cannot be started, so the car cannot protect itself.
     
    #5 fuzzy1, Feb 19, 2011
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  6. uart

    uart Senior Member

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    Yes park or reverse at any speed above about 7 km/hr will cause it to throw to neutral instead. But why bother when you can just hold the stick in neutral for about 1/2 to 1 second and do it the "correct" way.

    Also be careful with the "park" method. If you do it a too lower speed it will really go into park and it gives the transmission quite a shudder which cant be good for it.

    You can place the car into "N" at any speed and it's safe (with the one caveat given below). If you're going over 66 km/hr (41 MPH) when you throw it into "N" then it will idle the ICE in order to keep the MG1 speed under 6500 RPM.

    If you're gliding at 66 km/hr or less then it will leave ICE off when you go to "N". But here's the caveat, if you throw it into "N" at under 66 km/hr and then let the speed increase by coasting down a hill then you do run MG1 to more than 6500 RPM.

    I've heard that MG1 is apparently designed to be ok up to 10,000 RPM (but I dont know how good that information is) which corresponds to about 104 km/hr (65 MPH). Personally I don't like to go over about 85 km/hr (53 MPH) when gliding in "N", this limits the MG1 speed to about 8000 RPM.

    To take a look at MG1 speeds at various road speeds take a look at the eahart simulator here : http://eahart.com/prius/psd/
     
    #6 uart, Feb 19, 2011
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  7. Dolce_Vita

    Dolce_Vita Member

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    Thanks :) I find neutral particularly useful many of the 80km/h duel carriageway, 4 lane roads near where i live. Even though at these speeds it keeps the ICE at idle, it does seem to improve economy. There's one road where i did start my neutral glide at around 65km/h and ended up at 75km/h without the ICE kicking in, but i dont think that would have damaged it. I've recently been averaging 54.7mpg or 4.3l/100km, which is dissappointing as i averaged 61mpg or 3.8l/100km on a tank in late January, although my lifetime is still 4.16l/100km :)

    I'm seriously considering a PHEV kit soon, does anyone know if Plug In Supply ships/installs in Australia?
     
    #7 Dolce_Vita, Feb 19, 2011
  8. 2009Prius

    2009Prius A Wimpy DIYer

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    For short trips you may want to install an engine block heater to speed up warm up. Good luck!
     
    #8 2009Prius, Feb 22, 2011
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