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How far can you drive on the battery when the gas is gone?

Discussion in 'Gen 2 Prius Technical Discussion' started by HaroldMelamed, Dec 29, 2006.

  1. HaroldMelamed

    HaroldMelamed New Member

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    Just got my "new" 2005 Prius yesterday.

    It should take me a few months to figure out how to drive the thing. :)

    Anyways, how long will the car drive on the battery after I run out of gas?

    I'm one of those "Gas? It's not that empty" type people?

    Thanks much
     
  2. livelychick

    livelychick Missin' My Prius

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    <div class='quotetop'>QUOTE(HarryDriver @ Dec 29 2006, 08:33 AM) [snapback]368173[/snapback]</div>
    It won't. Sorry. I ran out of gas my first week. Because it's a synergy drive, I guess it needs both. I haven't tested this on a hill, though. It may work if you're going down hill...but then again, so would any car!!

    The good news is that the car beeps to tell you it's running low...and there's always the pulsing "last bar" of your gas gauge to remind you as well. Hope this helps.
     
  3. tomdeimos

    tomdeimos New Member

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    <div class='quotetop'>QUOTE(HarryDriver @ Dec 29 2006, 08:33 AM) [snapback]368173[/snapback]</div>
    You should never do it. When I am low I carry a can of gas with me. If you try to get somewhere on battery you are likely to cause some damage to the battery or be unable to start. There is no answer to the how far question since it depends where you are and what charge the battery was at. Here you will read about people that made it for a couple of miles, but you might not get 1/2 mile if there's even a small upgrade. All you can usually count on is enough power to pull over and park safely, on normal roads.

    There is also the 3 gallon minimum problem. I have run out and added a gallon without problem. Others tried to drive a bit and did that but could not start. The car needs to see over 3 gallons to know you added gas. If you drive enough so it gives up trying to start you may have to walk and lug a 3 gallon gas can.
     
  4. tumbleweed

    tumbleweed Senior Member

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    I agree with those who say just don't run out, it could cause problems. At the least you may need to put in 3 gallons to get it started again as tomdeimos said. There have been some old discussions on here about how far, it seems about 1 or maybe 2 miles at the most, but don't count on it.
     
  5. galaxee

    galaxee mostly benevolent

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    do yourself a favor and when the car says it's out of gas, stop on the side of the road and get some. it's not meant to be driven without gas- just like any other car.
     
  6. Oxo

    Oxo New Member

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    <div class='quotetop'>QUOTE(galaxee @ Dec 29 2006, 11:03 AM) [snapback]368203[/snapback]</div>
    Better still - get it filled when you begin to see only 2 bars. You'll get about 9 gallons in, possibly more and then you'll have no worries for well over 300 miles.
     
  7. DanMan32

    DanMan32 Senior Member

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    <div class='quotetop'>QUOTE(livelychick @ Dec 29 2006, 08:43 AM) [snapback]368177[/snapback]</div>
    That's just not true. MG2 can operate without the ICE as long as there is sufficient power in the main battery. Haven't you noticed the car driving without the ICE running?

    On a nominal 6 bar SOC, you can probably get 1-3 miles. The slower the speed, the better. Remember to turn the AC off to conserve battery power if you get into such an emergency.
     
  8. galaxee

    galaxee mostly benevolent

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    and get your wallet ready in case you have to pay to fly out the regional guy who has the HV charger...
     
  9. DanMan32

    DanMan32 Senior Member

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    <div class='quotetop'>QUOTE(galaxee @ Dec 29 2006, 11:16 AM) [snapback]368212[/snapback]</div>
    Discussed experiences suggest the car will power off before the HV battery will get dangerously low to the point it can't start the ICE. Now if you repeatedly restart it to try and get a few extra feet, then you might need that charger.
     
  10. galaxee

    galaxee mostly benevolent

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    you never know what people are gonna do in that situation, or any other for that matter, so i just say be prepared for the worst no matter what...
     
  11. mccorma1

    mccorma1 New Member

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    <div class='quotetop'>QUOTE(galaxee @ Dec 29 2006, 11:36 AM) [snapback]368246[/snapback]</div>
    I ran mine out of gas, and probably got about 3/4 of a mile -- didn't make it to the gas station, but one was in sight. I put less than a gallon in to get it started again, drove it to the gas station and filled it up the rest of the way. No dire consequences from it all (other than having to schlep gas around on the side of the road while late for a meeting).

    Obviously, the best advice is not to run it out. It's not really made to run on the electric motor for any significant distance. But should it happen, I don't think its quite as drastic as others who posted. I was able to start it with substantially less than 3 gallons and didn't have any battery problems.

    I think you always have about 50 miles once the pulsing last bar starts. I like to always get at least 500 miles on a tankful, so I usually wait for that. Silly, I know.
     
  12. dmckinstry

    dmckinstry New Member

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    <div class='quotetop'>QUOTE(mccorma1 @ Feb 4 2007, 05:24 AM) [snapback]385091[/snapback]</div>
    Similar experience for me. I got 522 miles on that tank of gas, and the last bar started blinking less than 10 miles before I ran out. I wasn't aware of how inconsistent the gas gauge was at that time. I probably got a mile (of which some was downhill). It stopped within a 100 m (a guess now) of starting back up the next hill. Fortunately I got a ride to the next gas station about 3 miles away. It was quite warm at the time (90F +).

    Dave M.
     
  13. jayman

    jayman Senior Member

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    <div class='quotetop'>QUOTE(HarryDriver @ Dec 29 2006, 09:33 AM) [snapback]368173[/snapback]</div>
    You can drive safely off the road, stop, power down, turn on the hazard flashers, and call for somebody to deliver a can of gas.

    For the life of me, I really don't get people who consistently run their gas tank down dry. Guess where the electric fuel pump lives? In the gas tank. Guess how it gets cooled and lubricated? By the fluid medium - the gasoline. Guess what happens when you run the tank dry? You run the fuel pump dry too. Do that often enough, don't cry when they have to drop the tank and replace the entire pump assembly.

    Now in the old days, with a mechanical fuel pump and a carb, you did no damage when it ran dry. You just added gas, and had to grind away at the starter until you filled the carb float bowl again.

    There is also a safety issue too.

    First, if you live in a large urban area with crime, you can pick and choose when and where to top off your tank, say at a station that has had very few carjackings/muggings and in the middle of the day when all the lowlife drug addicts are passed out. If you wait until Mr Blinky turns on, telling you that you're about to run out, you have to pick the first station you come to. If you happen to get mugged, while then in this case I have to put at least partial blame on the victim.

    Second, a full tank of gas is a good hedge if you have to evacuate. I seem to recall a certain large metropolitan area that had to evacuate due to a hurricane. If you're stuck in traffic with a tank 1/4 or lower, you won't get too far. Or up here, with winter and the possibility of being stranded in a blizzard, a full tank can literally save your life. It was -36 F this morning, even with a snowsuit, how long would you last without heat?

    Finally, just how much money do you "save" driving around with an empty gas tank? I've driven a lot of vehicles over +27 years, and I cannot recall one instance where I got better fuel economy with a tank below 1/4 than with a full tank.

    I'm sure you're a nice person and in no way am I knocking you down. I just don't get it.
     
  14. thpeaky

    thpeaky New Member

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    I am new on the forum so forgive me for jumping in.

    This is my second Prius. I ran out of gas once in my '01 and once I got gas had to go through a powering up sequence. I went about 5 miles on the battery but a lot of it was down hill. I learned my lesson on THAT car.

    NOW, on my '05, though I find myself getting to the point of the warning light coming on and it concerns me. I bought new tires at Christmas time and my mileage is WORSE not better as I had expected. I drive a whole lot as I am a therapist for a nursing home company and go to multiple buildings on top of my commute. Car is going in for a check up this week. I'd appreciate any advice.
     
  15. Bill Merchant

    Bill Merchant absit invidia

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    <div class='quotetop'>QUOTE(thpeaky @ Feb 4 2007, 03:23 PM) [snapback]385270[/snapback]</div>
    New tires + short trips + cold weather = poor MPG.

    What tires are you running now? What air pressure? The OEM Integrity tires, for all their many faults, are low rolling resistance. New tires are always a little stiff, and MPG usually goes up after a few thousand miles.

    And welcome to PriusChat!
     
  16. thpeaky

    thpeaky New Member

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    I bought Uniroyal Tiger Paws and I WILL check the pressure today. It is about 15 below here with the wind chill and my car is in a heated garage but I doubt if my pressure reading will be that accurate. I probably already have a couple of thousand miles on them. I am due for some service this week and will chat with my tech about the mileage. I have been getting about 42-43 and I WAS getting closer to 50-52 back in the Fall.

    Thanks so much!
     
  17. JimN

    JimN Let the games begin!

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    <div class='quotetop'>QUOTE(thpeaky @ Feb 5 2007, 10:19 AM) [snapback]385523[/snapback]</div>
    Lifetime I'm getting 49+mpg on the original Integrities. Now it is 18F and the MFD is under 49mpg so I'm expecting 40mpg on this tank. Increase tire pressure to 42/40 and block your grill. Otherwise you seem to be doing well.
     
  18. Warwind

    Warwind New Member

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    Yesterday I got to the point where my last pip had just started flashing. I usually try not to let it ever get that low, but this time it happened. I was on my way to the gas station at the time.

    I was feeling all nervous thinking the car was going to run out at any minute, but when I filled up, it would only take a little over 8 gallons. Does it sound right that when the last pip started flashing (~370 miles) I had anywhere from 2-4 gallons left?

    I know the gas tank is supposed to be 11.9 gallons, but I suspect I'm never getting anywhere near that in the tank when I fill up. 45 miles per gallon, @370 miles, is a little over 8 gallons used, so the math checks out for the distance I get on a tankful.

    So I guess my effective fuel capacity is somewhere around 9 gallons total, not 11.9.

    How far can other people go when the last pip starts flashing? I'd love to run it totally out one time, just to see how far it goes, but I know I won't try that...
     
  19. jayman

    jayman Senior Member

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  20. pviebey

    pviebey New Member

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    I pushed it once when I was late to meet my wife. Right at 500 miles, I figured I could go another 5 or so. It was not amusing to call my wife and tell her I was ummm stuck and to go home to get me unstuck. In pretty much middle of nowehere, FL.

    Happily, a 'state highway help' guy came by, gave me a gallon, and off I went.

    I think it's like asmall airplane, it indicates quite well when it's full, and anything else is chancy. And, like an airplane, there's a difference between 'useable' and 'capacity'. Ohhh, and ummm airplanes have bladders, it now occurs to me... So, I guess we just need to figure out what the real 'useable' is (and I wish they'd just quote that!)

    I get to the single block, I start thinking gas, when it blinks, I start really worrying. Try to avoid the worrying.

    PS: FWIW, I wouldn't carry a can of gas, especially in FL heat. In any accident, it could be bad.