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Gliding above 41mph

Discussion in 'Gen 2 Prius Fuel Economy' started by gazz, May 15, 2007.

  1. gazz

    gazz Member

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    I have noticed on my scangauge that when gliding above about 41mph the engine is turing at about 960rpm, and the mpg reads about 200mpg. I thought that although the engne was turing it was being driven by the electric motor and not using any petrol. Can anybody explain?
     
  2. Bob64

    Bob64 Sapphire of the Blue Sky

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    <div class='quotetop'>QUOTE(gazz @ May 15 2007, 04:27 PM) [snapback]442698[/snapback]</div>
    The fuel injectors doesn't inject any fuel. The engine is turned using momentum/the motors. Think engine braking.
     
  3. ken1784

    ken1784 SuperMID designer

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    <div class='quotetop'>QUOTE(gazz @ May 16 2007, 05:27 AM) [snapback]442698[/snapback]</div>
    My SuperMID knows it is complete fuel-cut.
    I've heard ScanGauge has the limitation on such situation.

    Ken@Japan

    Edit: additional information...

    http://www.cleanmpg.com/forums/reviews/t-c...ge-ii-4495.html

    "Another issue has to do with Fuel Cut. The ScanGauge II has no way to tell if the ICE is in Fuel Cut or if the car is at speed running at idle as you would in a NICE-On. Although the FE calculated and shown is very high under this condition (between 130 and 250 MPG depending on speed and ICE size), fuel is still shown being consumed when it is not thus causing an ever increasing error to build in. "
     
  4. gazz

    gazz Member

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    <div class='quotetop'>QUOTE(ken1784 @ May 15 2007, 08:44 PM) [snapback]442923[/snapback]</div>
    Thanks for that, could you tell me how quick you engine heats up in from cold. I am trying to find out if my car (UK) has the thermos. I have read it does not but the engine on the scangauge warms up very fast.
     
  5. JimboK

    JimboK One owner, low mileage

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    <div class='quotetop'>QUOTE(gazz @ May 16 2007, 03:48 AM) [snapback]443145[/snapback]</div>
    How quickly it warms depends on several things, including outside air temperature, how much the ICE runs during warmup, vehicle speed during warmup (which affects air flow through the grill), and how cold the ICE is to start (and the thermos coolant, if you have it). The US version of the car may take up to 10 minutes to get up to full operating temperature in cold weather.
     
  6. gazz

    gazz Member

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    <div class='quotetop'>QUOTE(JimboK @ May 16 2007, 06:09 AM) [snapback]443190[/snapback]</div>
    Yes I know it was probably a daft question, but I'm trying to find out if the car has a thermos, can you see it? of can you tell it is working?
     
  7. JimboK

    JimboK One owner, low mileage

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    <div class='quotetop'>QUOTE(gazz @ May 16 2007, 07:28 AM) [snapback]443195[/snapback]</div>
    To be honest, I've never been curious enough to want to see it, so I can't tell you what to look for and where. I'm sure someone on PC will know, or will know whether the UK version of the car has it. If you don't get an answer here, you might post the question as a new thread. Those with the answer won't see the question if they're not interested in the original topic here.

    Where you able to find an EBH? If so, between that and the ScanGauge you might have a hint. I notice a transient but fairly rapid and progressive drop in coolant temp on the SG in the first 30 seconds or so after a cold startup. My assumption is that there's a significant temperature gradient between the warm coolant in the block and what's in the thermos, now cooler after sitting all night. Then the SG temp briefly drops after the thermos dumps its coolant into the rest of the system.
     
  8. ken1784

    ken1784 SuperMID designer

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    <div class='quotetop'>QUOTE(gazz @ May 16 2007, 04:48 PM) [snapback]443145[/snapback]</div>
    You're welcome!
    In my understanding, the thermos is only available on NA Prius models.

    Regarding to warm up time, please refer to the following chart.
    The data was supplied by me and the chart is produced by Bob Wilson.

    The initial warming up (first 57 seconds) up to over 40C was done stand still. It consumed 44cc of gasoline.
    Then, I drove 4.83km until Prius moved to S4, total 222cc consumed.
    It was October last year. I don't remember the air temperature, but I think it was about 20C.

    Ken@Japan

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