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How much gas are you able to pump into Gen3 when empty?

Discussion in 'Gen 3 Prius Main Forum' started by iskoos, Dec 1, 2019.

  1. fuzzy1

    fuzzy1 Senior Member

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    Some of those roads simply don't have enough traffic to make a lot of money, that is why a number of previous stations are now closed.
    I don't. My cars (Prius and Subaru) can have DTE move faster, slower, or at nearly the same as the odometer, depending on conditions.

    The Subaru can actually have DTE increase along the trip on MPG-friendly days, sometimes even faster than the odo increases. OTOH, the Prius DTE is internally forced to shrink at least 1 mile per 2 miles driven, even on very long downhill fuel-less glides.
    Fat chance of that where and in the various conditions I drive, unless you have far better weather forecasting skills than me, including not just precipitation and snow-line elevations but also reasonably accurate headwind speeds all along the route. And can pre-adjust for seasonal and regional fuel blends on the fly.
    :rolleyes:

    One simply can't get the full flavor of our seasonally variable weather conditions in just a few months. Mother Nature just doesn't present all of them that close in time.
    :confused: Was this the first time you'd run down this low? All my cars had a learning curve to figure how much fuel was left at each low gauging point and indicator. As I learn a new car, I always add only a little more distance per refueling, keeping track of how much fuel it takes at each low reference point before pushing farther at a later time. And never ever push to new deep lows when or where the potential downtime matters very much.

    Good thing you weren't on that Nevada road pictured above when your warning appeared, you might have truly needed to turn back to the last passed fuel station, costing a lot more than a half hour.
    Then so did Ford and Honda and Acura and Subaru, from my first-hand experience.
    Most people put in barely 8 gallons because they refuel with several bars remaining, well before any sort of fuel warning at all, and don't want to get down to just 2 gallons remaining. Some have had personal experience with emergency evacuations, road closures requiring long waits or detours or simply quit and go back, etc. Or know of such cases.

    If you actually want to go to the 11 gallon point, fine, YOU STILL CAN! Just reset a trip meter either when the last bar starts flashing or when DTE first reaches 0, then use this guide right here, it has all the basic detail needed:
    [WARNING] Running out of gas (Gen III) | PriusChat
     
    #21 fuzzy1, Dec 3, 2019
    Last edited: Dec 3, 2019
  2. fuzzy1

    fuzzy1 Senior Member

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    That was a Gen2 risk. Gen3's traction battery is much better protected.
     
    #22 fuzzy1, Dec 3, 2019
    Last edited: Dec 3, 2019
  3. AzWxGuy

    AzWxGuy Weather Guy

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    I have never gone below a quarter tank. So I can't even play here, I'll see myself to the door :cool:
     
  4. CR94

    CR94 Senior Member

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    Plus about 2, if you patiently fill beyond the point the pump shuts off. However, that supposedly can damage (flood) the vapor recovery system. I stop 1.5 beyond shut-off.
     
  5. Johnny Cakes

    Johnny Cakes Senior Member

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    Thanks, that's the feedback I was looking for. And no one has disagreed with you!
     
  6. ASRDogman

    ASRDogman Senior Member

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    WHY would anyone want to risk running out of gas???? For their car that is. :)
    And if you wait long enough, and asked enough, you will eventually get the answer you WANT.
    Why would you want the correct answer? :)
     
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  7. Johnny Cakes

    Johnny Cakes Senior Member

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    This thread topic always brings them out. :)
     
  8. AzWxGuy

    AzWxGuy Weather Guy

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    It is just another form of record keeping. Like how many miles you got on your latest set of disk brake pads. We carry the used ones around in our pockets to show and tell at appropriate moments. Darn itchy asbestos. If you run your car out of gas, doesn't it have to be flat-bedded to the nearest dealer for a TechStream reset or some such? How about the leaning of the cylinder charges as gas starvation proceeds, burned valves maybe. I don't think the catalytic converter would like that either. It's probably harmless though. I would recommend a flexible bore scope that meets explosive environment ratings and peek down in the tank, into that low corner and see just how much gas you have left. Be close to a station when it's a tablespoon or less.
     
  9. fuzzy1

    fuzzy1 Senior Member

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    A few people who tried too many restarts before adding any or enough fuel, found further start attempts locked out and had to get tows to a shop for reset.

    Then others found that simply disconnecting the 12V battery long enough to forget its retained memory, did the same thing.

    Others were able to add fuel and get going just fine without the too-many-attempts lockout.
     
  10. Maarten28

    Maarten28 Active Member

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    Except for my first fillup (which was when I bought it) and one time shortly after it (when I had 9.996 gallons and was still learning about the intricacies of the fuel indicator) I never had less than 10 gallons on a fillup.
     
  11. kc5dlo

    kc5dlo Active Member

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    About 10.5 gallons on several occasions. I have read on this forum many times that there is about 100 miles of driving available after the last tic of the gauge starts blinking. I have taken it to about 90 before I chicken out and pay what ever the price is. I usually will not buy gas til on the last tic of the meter if I am in a familiar area and 2 tics when not. This is the only car I have ever owned that I have not run out of gas.
     
  12. tonynap

    tonynap Member

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    + 2 gallons after shut off since I got the car, no problems ever.
     
  13. Grit

    Grit Senior Member

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    Holy moly, so you pumped in about 13.4 gallons in? How many miles driven from the last 13.4 gallon tank from F to E?
     
  14. ASRDogman

    ASRDogman Senior Member

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    So the filler neck is 1.5 gallons?
     
  15. tonynap

    tonynap Member

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    As info, my car has commuted 50 miles each way for it's whole life. Add any around town mileage during the week and I'm looking at between 500 and 550 miles for the week. This makes it a good car to use for discussion based on 11.9 gallons in the book and 51 MPG on the sticker, putting a 'by the book' number at 600 miles per tank.

    That lines up with my experience with fuel. The sticks on the gauge are a gallon each, or 50 miles. I get the beep and the flash on Friday on the way home, and figure 100 miles. I've never run out.

    The average week ends at around 525 miles on 11 gallons. Pump handle clicks off at 9. I add 2.

    YMMV . . .
     
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  16. Robert Holt

    Robert Holt Senior Member

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    I believe the extra fuel above the 11.9 gallon listed capacity of the tank is both the volume of the filler neck and the volume of the evaporative canister that I believe will catch the overflow and recycle it, although possibly being damaged in the process.
     
  17. ASRDogman

    ASRDogman Senior Member

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    I am refering to this from Grit: Holy moly, so you pumped in about 13.4 gallons in? How many miles driven from the last 13.4 gallon tank from F to E?
    11.9 is the USABLE fuel, they don't count the filler neck because you supposed to fill the neck until it overflows.
    So if as tonynap said: "+ 2 gallons after shut off since I got the car, no problems ever"
    So it would actually be 13.9 gallons, to overflowing. Which isn't good.
    So I think maybe the fuel pump is not correct. I don't really thing the filler neck is 2 gallons, even with the overflow.
    But, I could be wrong.....
     
  18. tonynap

    tonynap Member

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    I got the flash this morning about 25 miles into the commute. I finished my commute (another 75 miles) and then got gas.

    I put in 10.8 gallons before the handle clicked off, then continued to fill, finishing up at 12.949 gallons.
     
  19. Robert Holt

    Robert Holt Senior Member

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    Interesting! Suggests that the capacity of the filler neck above the normal click-off point plus evaporative canister is maybe 1 gallon total.
     
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  20. Grit

    Grit Senior Member

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    Ah, this is the reserve amount that one person said on here before.