How far can I drive while the low fuel light is on?

Discussion in 'General Motoring' started by CWD, May 26, 2006.

  1. CWD

    CWD Guest

    My car is Hyunday Elantra VE 2005, the fuel tank is 55L, while the low fuel
    light it on, normally I can add about 40L gas. Since there's about 15L gas
    left in the tank, I can still drive at least 100Km in local without any
    refill, am I right?
     
    CWD, May 26, 2006
    #1
  2. CWD

    Jack Cassidy Guest

    Maybe.
    Jack Cassidy
     
    Jack Cassidy, May 27, 2006
    #2
  3. You can drive until the car suddenly stops, at which point you'll get
    out and kick yourself in the ass as you walk to the nearest gas station.
     
    Brian Nystrom, May 27, 2006
    #3
  4. CWD

    Zotto Guest

    Better not doing more than 50 Km.. if you remain without fuel the pump
    could break, and it's very expensive.
     
    Zotto, May 27, 2006
    #4
  5. CWD

    Raoul Guest

    How gutsy do you feel? The most I ever pushed it was when it took 11.4
    gallons to fill my, IIRC, 12 gallon tank in my 03 Accent. I don't
    recall the distance I had driven, but it must have been close to 400
    miles.
     
    Raoul, May 27, 2006
    #5
  6. CWD

    Matt Whiting Guest

    Any evidence that this is true?

    Matt
     
    Matt Whiting, May 27, 2006
    #6
  7. CWD

    Zotto Guest

    Read the instruction manual, they recommend to fill the tank asap when fuel
    light is on..
     
    Zotto, May 27, 2006
    #7
  8. CWD

    Mike Marlow Guest

    Yeah, but that's for the idiots who can't figure that out on their own.
    There's a ton of stuff in owner's manuals that shouldn't have to be said and
    that pose no threat to the car.

    Having said that, most in-tank pumps are cooled by the liquid in the tank
    and it is advisable to keep the level above a quarter tank or so.
     
    Mike Marlow, May 27, 2006
    #8
  9. CWD

    Matt Whiting Guest

    Sure, you don't want to run out of fuel. Does the manual say that not
    doing so will harm the fuel pump? I don't recall seeing that when I
    read mine back in December.

    Personally, I believe this is largely an urban legend. Maybe there are
    some poorly designed electric fuel pumps out there, but most are cooled
    by the fuel running through them, not the fuel they are immersed in.
    So, as long as you have fuel, you have coolant for the fuel pump. And
    once the fuel is gone ... the engine quits and there isn't much need for
    the fuel pump then. :)

    This myth has been perpetuated by a lot of organizations who should know
    better (AAA for one), but that doesn't make it true. AAA also says that
    running low on gas will cause the pump to pick up sediment in the bottom
    of the tank. Do they really believe that the fuel pickup, which is
    located near the bottom of the tank, knows how much fuel is above it and
    thus will only pick up sediment from the bottom when the fuel level is
    low? Reading this sort of stuff is a hoot.

    Matt
     
    Matt Whiting, May 27, 2006
    #9
  10. CWD

    Matt Whiting Guest

    I'm still looking for some credible evidence that this is true.
    Credible, means it doesn't come from AAA, or your brother-in-law, etc.
    If it comes from a fuel pump manufacturer, fuel pump designer, car
    maker, etc., I'd consider that reasonably credible. I've never yet
    seen anything for any vehicle I've owned and, in fact, have some
    evidence to the contrary. Admittedly, not a lot of evidence, but some.

    First evidence is that I routinely run my vehicles down below 1/4 tank
    or occasionally until the low fuel light comes on. I've run several
    cars over 100K miles and have had only ONE electric fuel pump failure.
    That was on a 96 Plymouth Grand Voyager that had in the neighborhood of
    150,000 miles at the time of failure.

    Second evidence comes from a guy who was a fuel pump designer for a
    number of years and said that the fuel pumps are cooled by the gas they
    are pumping (they pump the gas around the electric motor typically), not
    the gas around them in the tank. It also comes from common sense.
    Anyone with half a brain knows that moving a liquid past a source of
    heat is much more effective for cooling than depending on relatively
    still coolant. That is why cooling fans exist, why water pumps exist,
    etc. Using the fuel around the fuel pump as coolant would be much less
    effective as you'd be depending on the sloshing action alone to move
    heat away from the pump. If the car is sitting still, this would not be
    very effective. Pumping the coolant through the pump is the smart way
    to do it, and the way every fuel pump I've seen has been designed. This
    way, as long as the pump is running, a moving stream of coolant will exist.


    Matt
     
    Matt Whiting, May 27, 2006
    #10
  11. CWD

    Zotto Guest

    May be the point is that if you run with very few gasoline the pump could in
    some moments to have cavitation picking up air bubbles instead of gasoline
    and this is not good for lubrication inside the pump itself.
    I have LPG on my Sonata and the LPG manifacturer recommends to keep in
    gasoline tank at least 1/4 of capacity, even if I could run my engine
    without any gasoline, using LPG.
     
    Zotto, May 27, 2006
    #11
  12. CWD

    Matt Whiting Guest

    I'm not familiar with LPG systems so I have no idea why that
    recommendation. I just spent an hour reviewing the fuel system section
    in the Sonata shop manual (official Hyunday manual set) and there is no
    mention of keeping any minimum amount of fuel in the tank.

    Matt
     
    Matt Whiting, May 28, 2006
    #12
  13. CWD

    Zotto Guest

    Zotto, May 28, 2006
    #13
  14. CWD

    Matt Whiting Guest

    Remember, I specifically said credible sources. This is just another
    person passing on the old wives tale. And even the grammar in this is
    atrocious. I'm guessing this guy didn't make it past 8th grade.

    I really like the "running completely out of fuel running out of fuel
    allows the electric fuel pump to run "dry" which nearly immediately
    ruins the pump." comment. I've run my Chevy pickup completely dry
    several times (I used to carry a 50 gallon tank in the back to refuel my
    airplane, so I always had gas available handily). My truck has nearly
    100K miles on the original fuel pump. So much for the "immediately
    ruins the pump" theory.


    Matt
     
    Matt Whiting, May 28, 2006
    #14
  15. CWD

    Mike Marlow Guest

    That I cannot provide. Like you I dismiss the AAA suggestions and all of
    the other completely unfounded stuff and do look for some credibility, or
    some other assurance that the story is coming from a source that I can
    trust. For the most part, I've been hearing this for a while now within the
    auto-repair circles. From folks dealing with this stuff every day. I've
    never heard a design engineer state it, or the manufacturer themselves, but
    it is a concept that at least makes sense.
    I've had a couple of GM pump failures. Like you, my cars stay in the family
    for a long time. My failures have generally been upwards of 100,000 miles.
    I make it a practice to keep 1/4 tank full but that's a longstanding habit
    and a reflection of where I live. We are subject to condensation in the
    tank and ice in the winter. Dry gas fixes this, but so does keeping a
    sufficient level in the tank.
    Actually - that does make a great deal of sense.
     
    Mike Marlow, May 28, 2006
    #15
  16. CWD

    Zotto Guest

    Better so, then. One thing less to be worried about :)
     
    Zotto, May 28, 2006
    #16
  17. CWD

    Matt Whiting Guest

    That was my reaction. When you have a choice to use gas just sloshing
    around the pump or a constant stream of gas flowing through the pump, I
    really believe that the design engineers are smart enough to choose the
    latter. That doesn't rule out some cheap design from somewhere that
    isn't well-designed, but I'm guessing that most quality conscious auto
    makers would have eliminated those suppliers long ago.

    Matt
     
    Matt Whiting, May 28, 2006
    #17
  18. CWD

    Matt Whiting Guest

    What is a Sonica? I see that in your .sig. The pictures seem to show a
    Sonata. Does Hyundai use different model names in different countries?

    Matt
     
    Matt Whiting, May 28, 2006
    #18
  19. CWD

    Zotto Guest

    Yes, in Italy Sonata is named Sonica, as "sonata" in italian means not only
    a musical form but also something like "cheat"...
     
    Zotto, May 28, 2006
    #19
  20. CWD

    jtees4 Guest

    Usually around 30-40 miles. Of course, after that, you can still drive
    all you want...it's just that the car won't be moving anymore and
    you'll look pretty silly.


    Never Forget!!!
    http://www.september11victims.com/september11Victims/VictimInfo.asp?ID=2654
     
    jtees4, May 28, 2006
    #20
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