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Is the ICE really off?

Discussion in 'Gen 3 Prius Technical Discussion' started by Jim Calvert, Oct 9, 2009.

  1. Jim Calvert

    Jim Calvert New Member

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    How can I tell when the internal combustion engine (ICE) is really off while the vehicle is under way? By "really off", I mean when it is not consuming fuel, not idling, and the pistons are not moving up and down.

    Does the instrument panel show this? If so, please explain.

    If the instrument panel does not show this, is there some kind of indicator that I could fabricate and install that would provide an "ICE Really Off" indicator?

    Thanks,

    Jim
     
    #1 Jim Calvert, Oct 9, 2009
  2. fuzzy1

    fuzzy1 Senior Member

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    An incomplete list:

    (1) ScanGauge-II, or other engine monitor, that can display RPM (for pistons moving) or GPH (for fuel being consumed);

    (2) Ken1784's (Ken@Japan) LED ICE indicator, which really indicates when the fuel pump is running. Sorry, a very quick search didn't find the right thread;

    (3) Speedometer. At 46 mph and higher, and gear selector in D, the pistons are moving, whether fueled or not.
     
    #2 fuzzy1, Oct 9, 2009
  3. ken1784

    ken1784 SuperMID designer

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    The standard instrument can't show real ICE off status.
    My understanding is ScanGauge-II has some limitations.
    At 46 mph and higher, the GPH shows some numbers on the complete fuel cut mode on downhill.
    Please correct me if I'm wrong.
    Unfortunately, my ICE running monitor LED also can't detect the fuel cut mode above 46 mph.

    AFAIK, the only way to detect fuel burning is picking up the raw fuel injector signal.

    Ken@Japan
     
    #3 ken1784, Oct 9, 2009
  4. David Beale

    David Beale Senior Member

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    The Scanguage II -can- be forced to tell the truth, but it's not easy and may not be repeatable. But mine will sometimes show 0.2 l/hr and that's zero. The engine doesn't consume that small a quantity at -any- time. Unless there's a leaking injector. ;)

    The Scangauge II will display RPM and that reading -IS- accurate. It's a 1/2 to 1 sec. average though, so you'll not get -instant- indication.

    But the big question is has the Scangauge II been working properly yet with the GIII?

    Eventually you will learn to "feel" when the ICE is running. Took me a while with Pearl.
     
    #4 David Beale, Oct 10, 2009
  5. spinkao

    spinkao New Member

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    I simply look at the instant consumption meter if I am not sure. When it shows 0.0l/100km (in your case probably infinite MPG or some threshold value, like 100MPG) you can be sure the engine is not burning any fuel. The pistons would move if you are moving faster then warp speed, but no gas is flowing in. The indicated value has some time lag as the MFD is not really a "real-time" indication, but it is good enough.
     
    #5 spinkao, Oct 10, 2009
  6. Jim Calvert

    Jim Calvert New Member

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    Thank you all for your responses.

    So it looks like there is no sure way to know if the ICE is "really off". Perhaps I could install a small video camera pointed at the crankshaft.

    No, just kidding, but it is dissapointing to find out that "really off" cannot be easily detected.

    Jim
     
    #6 Jim Calvert, Oct 10, 2009
  7. a64pilot

    a64pilot Active Member

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    That wouldn't be hard to do unless I don't understand the system. Question is, what does it do for you other than satisfying curiosity
     
    #7 a64pilot, Oct 11, 2009
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