Any issues with EV driving with the Low Fuel Light for a long period?

Discussion in 'Prime Main Forum (2017-Current)' started by noonm, Nov 4, 2019.

  1. noonm

    noonm Active Member

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    Finely had the 'low fuel light' turn on for my current tank of gas. However, as my regular driving involves almost exclusively 100% EV driving, I can feasibly continue driving for weeks (or months) without having the refuel.

    My question is:
    • Presuming the engine never turns on, is there any risk to me continuing to drive in 100% EV mode with the 'low fuel light' on?
     
  2. bisco

    bisco cookie crumbler

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    nope

    just don't get caught needing to go along way and no time for gas

    but you probably still have 2 gallons in there
     
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  3. Dimitrij

    Dimitrij Active Member

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    I would say Toyota is very cautious with its fuel gauges; even though on a few occasions I drove 8-10 miles past the "0 miles" warning, I have never been able to cram more than 8.3 gallons of gas into what I believe to be a 9.5-gallon tank ... the way I drive this translates into "0" being something like 75 miles worth of range.

    That said, I wouldn't push my luck any further than I have.
     
  4. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    You are reducing the choices the computer has to protect your car. You have to ask yourself, Why?
     
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  5. Prime8

    Prime8 Member

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    I believe that the low fuel light turns on when you have 30-50 miles of reported distance to empty on gasoline. Once your distance to empty reaches 0, you still have 1 gallon of gasoline left. I usually reset my trip B and I know that I will run out of gasoline when trip B and the trip B fuel economy are the same number. Make sure you have electricity left, and switch to EV only mode when you run out of gasoline.

    I have run mine out of fuel 3 times, and I used the electricity that I held in reserve to arrive at the Costco gas station that was my intended destination. I only drive long distance and it is critical that I know exactly what I can and cannot do. When the Prime runs out of fuel, it goes into a mode where it appears very under powered until you switch to EV mode. Once you switch to EV mode, it drives normally.

    Once you put fuel back in it, it just acts normally like nothing happened.

    When you finally run a Prime out of fuel, you should be able to put 11 gallons in it. The rated capacity of the tank is 11.3 gallons.
     
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  6. schja01

    schja01 One of very few in Chicagoland

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    Generally it’s a better idea to keep the tank full. Less condensation especially in winter. At least that was the recommendation.
     
  7. VTBIGDOG

    VTBIGDOG Active Member

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    When you let the fuel get that low you are actually causing the fuel pump to suck air. That's a sure fire way to shorten the life of your fuel pump which is not an inexpensive part.
    Posted via the PriusChat mobile app.
     
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  8. Salamander_King

    Salamander_King Senior Member

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    Don't think so. As @bisco said, the low fuel light on means there is still ~1.7gal in your tank. Conservative HV driving will give you at least 90 more miles of range.
    But do you really want to keep staring at the low fuel light every day?

    Screenshot 2019-11-05 at 4.04.58 AM.png
     
  9. Rob43

    Rob43 Senior Member

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    I recently drove about ~70 miles at ~70 MPH on the low fuel light, 100% ICE.....



    Rob43
     
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  10. FuelMiser

    FuelMiser Senior Member

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    You must have a very high tolerance for anxiety! A steady yellow light on the dash would drive me nuts. Of course, I'm a former military pilot, so warning lights really bother me.
     
  11. bisco

    bisco cookie crumbler

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    nothing like real world testing (y)
     
  12. bisco

    bisco cookie crumbler

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    i fill up to 3 gallons, and refuel when the light comes on. i have read that condensation isn't a problem in these sealed systems?(n)
     
  13. Trollbait

    Trollbait It's a D&D thing

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    Presumably, you'll get the big warning message when the car actually runs out of fuel, so I see no risk with just having a the low fuel light on.
    However, colder weather will be here soon, and that means shorter EV range with the ICE more likely to come on for heat and defrosting.

    Because of emission regulations, gas tanks are now far better sealed than in the past. Besides, the ethanol will remove any water that manages to get in.;)
     
  14. VTBIGDOG

    VTBIGDOG Active Member

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    I don't dispute what you're saying about the low fuel light coming on. The previous poster stated that he lets it run out of fuel which is a totally different situation
    Posted via the PriusChat mobile app.
     
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  15. Salamander_King

    Salamander_King Senior Member

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    Yeah, I know what you mean. My response was directed to OP not to your comment. Sorry for the confusion.;)
     
  16. frodoz737

    frodoz737 Top Wrench

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    This infatuation with and/or justification of running on or near empty escapes me.
     
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  17. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    It could be worse, one year we had a poster enraged he was not rewarded for running out of gas routinely.
     
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  18. noonm

    noonm Active Member

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    Don't get me wrong, I understand the sentiment, but I have a particular reason to push the limit....

    The Race for 500mpg!
    [​IMG]

    I know its a bit of a fiction, as its not the true "mpg for a single drive", but because its on my dashboard, I really want it to read 500mpg before I fill the tank.
     
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  19. bisco

    bisco cookie crumbler

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    and i want a pic (y)

    and, oh yeah, i'd be all over that
     
  20. Salamander_King

    Salamander_King Senior Member

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    To reach 500mpg at the current use of gas, you would need to drive to 4602miles.
    That would be only 317 miles more.

    At 30 miles EV per charge/day, you only need 11 more days.
    Go for it.
     
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