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No ICE "Cycle" Required w/ "Warm" Power On!

Discussion in 'Gen 3 Prius Main Forum' started by a priori, May 29, 2009.

  1. a priori

    a priori Canonus Curiosus

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    Did anyone know this had changed? This is one of the very pleasant surprises to me.

    I suspected something had changed, and then began to follow the Power on activity more closely. Sure enough: If you re-start a warm engine, by this I mean go from "Off" to "Ready" when the car has fully warmed, then the ICE does not need to turn on and go through its "cycle" of operation.

    If I am understanding this correctly (or even anything close to correctly), then one of my pet peeves is answered! I just hated stopping at a store for 50 seconds and powering down a warm car, because at start up it would turn on the ICE and start the whole process over again. It appears all of this has changed, though I imagine we'll need more astute observations (Scangauges, etc.) to confirm.

    The only "proof" I can share is that I could immediately drive away in "stealth" mode after powering on. No ICE cyclying; no need to drive and stop for 7 seconds; immediate access to electric mode (without pressing the EV Mode button).

    I did this yesterday and took photos of the 1-minute and 5-minute consumption screens. You can tell I just powered the car on, because of the absence of older data on the screen. (Well, that or I sat in the car with it powered on and motionless for at least 25 minutes!)

    Here are the pics:

    DSCF6867.jpg

    DSCF6868.jpg

    Perhaps I've misunderstood what is happening, and I'll defer to the more knowledgeable, but I think my interpretation is correct.
     
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  2. NYPrius1

    NYPrius1 Active Member

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    WoW, This Is Nice to know!
    Thanks
     
  3. ljbad4life

    ljbad4life New Member

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    it proabaly has to do with the tailpipe heat recapture. in the Gen II prius the second you shut off the car it pumped the fluid into the thermos.
     
  4. a priori

    a priori Canonus Curiosus

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    That may be part of it, but it also seems to me there is a change in the programming of the ECUs.
     
  5. ljbad4life

    ljbad4life New Member

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    wow that didn't occur to me, my line of thinking was moving the fluid uses energy and it causes the fluid to cool (a bit) before it goes into the thermos. so the car upon start would have to reheat the fluid (only slightly). which would explain theshort run time for the ICE, but I think it is probably the updated ECU more than anything.
     
  6. jprates

    jprates https://ecomove.pt

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    European models have always behaved like this.

    Don't know what was the reason for yours 2G to behave differently in the first place :confused:
     
  7. usbseawolf2000

    usbseawolf2000 HSD PhD

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    Thanks for confirming.

    I am still wondering the ICE ignition timing during the warm-up process. My guess is that it will no longer do the negative timing.