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Drive till out of gas

Discussion in 'Prius c Fuel Economy' started by Derek McCarra, Aug 6, 2017.

  1. Sam Spade

    Sam Spade Senior Member

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    Yep, this is a free country.
    People are free to be as stupid as they want.
    This strikes me as a perfect example.......two of them actually.

    Honestly, you seem to KNOW that neither of those practices are good ideas and yet you persist in doing them.
    Why is that ??? Especially when neither one accomplishes anything really useful.
     
  2. ztanos

    ztanos All-around Geek!

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    I've heard they aren't good practice and yet I've been presented with absolutely zero evidence of it on a car that is not older than 2005. I've heard a few, "I had a friend who had a friend who had to replace the fuel pumps" though.
    Honestly, I'm lazy and I don't like stopping for gas a lot. That's why I do it. I also know that if I do have an issue, I know how to fix it and will do so accordingly. I had over 180k miles on my 2001 Saturn and I did the exact same behavior on it. Transmission issues, yes... emissions/fuel pump issues. Nope.
     
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  3. fotomoto

    fotomoto Senior Member

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    Get a plug-in. Most years I only stop 2-3 times for gas.
     
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  4. ztanos

    ztanos All-around Geek!

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    I've considered it. When I bought this car, my commute was 100 miles/day with no opportunity to plug in during the day. Now I can, but the car is paid off and it is hard to think about having a car payment again. :(
     
  5. fuzzy1

    fuzzy1 Senior Member

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    Maybe because one of PC's resident 'stupid people', Bob Wilson, repeatedly ran his first two Prii dry more than 50 times as part of his other engineering tests, and was unable to verify this supposed failure mechanism?

    I was using him as my 'canary in the coal mine' on this issue. That canary survived to retirement.

    BobW has reported vast amounts of useful technical information back to these Fora.
     
  6. TheTimob

    TheTimob Member

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    If your idea of fuel economy is miles per tank rather than miles per gallon, then you've bought the wrong car! A Prius C holds only 9.1 gallons. The Ford F-150 pickup truck has a 36 gallon tank as an option to do over 700 miles per tank. :D

    It's like Nissan's ads about the altima going so much farther than any competitor on a tank of gas - but they don't mention that the tank is 20 gallons! Technically the statement is true, but it is very misleading.
     
  7. Sam Spade

    Sam Spade Senior Member

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    Another case of "I (and Bob) have never seen it so therefore it must not exist". Bad logic.
    A lot of people shoot up heroin and they don't die; maybe you should to. :eek:
     
  8. fuzzy1

    fuzzy1 Senior Member

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    I have already disclosed seeing it twice, back in post #18 of this thread.

    But the various circumstances are leading me to consider the possibility that these warnings are overblown.
    Maybe you should take your own advice, while I stick to mine.
     
  9. ztanos

    ztanos All-around Geek!

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    Only 9.1 gallons? Yeah... that's not right.
     
  10. Sam Spade

    Sam Spade Senior Member

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    But there is NO GOOD REASON TO RUN YOUR TANK DRY.
    Your business about coming up with some kind of scientific data is just a smoke screen.

    A small chance is not NO chance.......and when there is nothing useful to be gained, why take the chance at all ??
     
  11. TMR-JWAP

    TMR-JWAP Senior Member

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    Only 9.1 gallons? Yeah... that's not right. Prius C.png

    He was off by a mile !!!!! It's 9.5 gallons.....
     
  12. fuzzy1

    fuzzy1 Senior Member

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    (1) That is your opinion, not a fact;

    (2) BobW has posted many interesting and useful technical findings over the years. Many of these involved comparisons of different fuels. Such comparisons demand draining Sample A out of the tank before inserting Sample B or Sample C, as mixing them together seriously complicates the comparisons. The most expedient way to drain the fuel, was to simply burn it off until engine starvation;

    (3) I run a tank completely dry no more than once per car, and only at a time and place of my choosing, preselected for my convenience. This helps refine the real fuel gauging of my car, greatly narrowing the initial 2+ hour range uncertainty. If commercial airliners with hundreds of people aboard typically land with considerably less than two hours of fuel range remaining, then I'm not taking any sh*t from folks who insist that I should set aside 2+ hours of fuel to never be used;

    (4) The rest of the time, I run the tank low -- NOT THE SAME AS DRY -- when it suits my desired use, which is definitely not even close to every tank. This also keeps me in practice for any repeats of past geopolitical and/or rural events that caused fuel refills to be unavailable or subject to serious price gouging. Remember, I've BTDT;

    (5) I didn't suggest that you try something with a significant fatality rate. The next time you suggest that to me, I may hand you some live ammunition and suggest you try some Russian Roulette. In your own words, a lot of people try it and don't die.

    You are now sounding like a denier.

    I invite you to search back on Bob Wilson's very many reports to PriusChat, on his engineering findings that involved running his tank dry as part of his test setup. Smokescreen? Pure BS.
     
    #32 fuzzy1, Aug 9, 2017
    Last edited: Aug 9, 2017
  13. The Electric Me

    The Electric Me Go Speed Go!

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    IMO purposely running ANY vehicle out of fuel is rarely a good idea.
    And with a Prius...your range is great, even if take heed to the warning and gauges conservatively.

    My feeling also was, that with a Hybrid, Hybrid Synergy Drive....predicting how far you may or may not be able to go with any remaining fuel is very difficult. Because Hybrids don't burn fuel consistently. How much fuel a Prius may or may not use, in any give distance or situation can and will vary with the addition of many different factors. You are driving a vehicle designed to be efficient, both in fuel economy and also tail pipe emissions. What this means is 1 1/2 gallons of gas remaining in a Prius...and how far that might get you, can fluctuate greatly.
    Driving a warmed up Prius, on a day where the temperature outside is moderate in conditions promoting fuel economy, that is not too much stop and go, flat or even downhill driving...will get you much farther than the same 1 1/2 gallons, with a Prius on a cold day, trying to warm up and keep it's engine warm, perhaps driving a lot of stop and go, and/or uphill.

    Therefore, while I set a average distance I felt I could extrapolate from the reported MPG and probably safely go, since the Prius's driving range was so good in any case, it just seemed much wiser to simply fill up.....when the Prius warned it was about time to fill up.

    If I did so? And it turned out I only added 8 gallons? Well good for me, good for Prius, and good for the bank account.
    All good, and much better IMO...than running an unneeded experiment on running the fuel dry.
     
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  14. ztanos

    ztanos All-around Geek!

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    In the words of the venerable Dominic Toretto. It doesn't matter if you win by an inch or a mile. Winning is still winning. :D
    Thank you for the exact number, I couldn't remember, I just knew that it wasn't 9.1 considering my average fill-up is currently at 9.28 gallons.
     
  15. ztanos

    ztanos All-around Geek!

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    I'm not sure if you're referring to me, but I've never run my tank dry, just low. Even going 50 miles after the beep, there is still ~1/3 of a gallon in the tank. The modern fuel pumps get more cooling by fuel inside the pump and a marginal amount of cooling by the outside liquid.

    In our car, 1/3 of a gallon is still 17 miles and that's assuming I'm only getting 50 mpgs. :D See, plenty of buffer.

    But in all seriousness, only 2 cars showing evidence (based on this thread only) is more likely to suggest that the fuel pump would have failed no matter the use case.
    Also, I am not telling anybody to do what I do. I know my car and trust my car... so far she hasn't let me down. Same for my other car, and the car that Pepper Bomb replaced.
     
    #35 ztanos, Aug 9, 2017
    Last edited: Aug 9, 2017
  16. Sam Spade

    Sam Spade Senior Member

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    We were not and are not talking about Bob.
    You implied that YOU running the tank down really low was somehow similar to what Bob did.
    It isn't even close.

    I quit. Pointless.
     
  17. Sam Spade

    Sam Spade Senior Member

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    That comment said "you" and it was attached to a quote that was NOT from you.
    Who do you think I was referring to ??
     
  18. TMR-JWAP

    TMR-JWAP Senior Member

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    Sam,

    Although I agree about the low level cons, the world would be a boring place if we were all the same. Zt has it in his mind that his way is the way to go (for him). No one is going to change his mind. Just like no one will ever convince me that I should run my tank until it only has 1/4 gallon remaining. To me, the risk of something stupid happening is not worth it. I've been in winter climates where I would fill up at half tank, just to make sure I had plenty available in case something happened. Years (decades) ago, driving I-80 through Pennsylvania during a heavy snow, had a transmission fail. Was very thankful for having plenty of gas while we sat there on side of road, idling for 3 hours. I've also been in a car that ran out of gas on the New Jersey Turnpike where traffic was flowing at 75+ and my friend wasn't able to get to the shoulder before the car stalled. Crappy situation that could have easily been avoided. Put a lot of lives at risk. Young and dumb.

    As for Zt, to each his own. I'll stick with doing my prii fill-ups at one dot during fair weather seasons and two dots in cold weather seasons. Everyone has their own preferences.
     
  19. CoastRider

    CoastRider Active Member

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    Lately, I've been topping off the tank when it's only 1/4 down. I like the hot dogs at the gas station. :cool:
     
  20. royrose

    royrose Senior Member

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    This is an all too common occurrence of someone starting a controversial thread that gets lots of comments but the OP never returns. A bit troll like IMHO.
     
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