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Running out of gas on purpose

Discussion in 'Gen 2 Prius Technical Discussion' started by berinker, May 3, 2008.

  1. Winston

    Winston Member

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    Please post the results of your experiment.
     
  2. turboj91

    turboj91 Junior Member

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    I have an 02 with 145K on the clock. I also wanted to know what my range would be once I heard the warning beep and had the one blinking pip. To determine this I just got to a gas station almost immediately (as many times as this was possible) upon the notice of the blinking pip and filled the tank. I bet I have done this at least two dozen times and each time I determinted that I had 3 gallons left. A couple of times I had to drive quite a ways with the blinking pip. I was comfortable knowing I had 3 gallons. The additional fuel at the eventual fillup was in line with the extra mileage driven from when the pip started blinking.
     
  3. GoCarGo

    GoCarGo In the pool

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    Funny the coincidence of this thread and my running out of gas today, quite by negligence in my newish '08. The guage has been blinking for about 3 days now and have basically been putting off refueling due to my only running short 3 to 5 mile trips, mentally figuring that each little rectangle represented one gallon, ie 45 or so miles.

    Anyway, the saftey red triangle warning light came on the dash and began beeping.. which the beeping was quite strange to me since I've performed the (no) beeping mod 2 months ago. I was 1/2 mile from gas station with good battery charge and pulled in, filling up 10.951 US gallons. Turned on, and saftey light still on, I shut off.. waited 2 minutes, repeated and all was fine.

    Bottom line is I traveled 55 miles flashing.
     
  4. fthorn

    fthorn From gas hog to greenie to gas hog

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    there's a new website you can check and contribute to now for gas gauge accuracy.

    Tank on Empty: Home

    [​IMG]
     
  5. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Amusing graph that is strangely accurate because they don't identify "first time" versus "other times:"

    • 130 miles - first time I ran out of gas
    • 60-70 miles - median for other times
    • 30 miles - shortest distance on 'flash'
    Bob Wilson
     
  6. Scruge

    Scruge New Member

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    I've never run out of gas in 40 years of driving until I owned a Prius.

    We took our 2008 with 2500 miles on its first out of town trip this past weekend, Houston to New Orleans. 365 miles.

    We top the tank off the day before and I figure there is no need to fill up again until N.O.

    WRONG... we ran out of gas 6.7 miles short of our hotel in N.O., in a construction area on I-10 without a shoulder . The engine shut off and the dash board lit up with malfunction indicators, one being a flashing "E" on the fuel gauge. Our speed dropped to 54 mph. I quickly fumbled through the electronic touch screen controls trying to shut down the A/C to conserve power. We were in the inside lane and needed to cross 3 lanes to move right in hopes of finding an exit before the batteries gave out. By the time we made it to the far outside lane our speed was down to 44 mph. About a 1.25 miles later we found an exit and limped off at 30 mph. Unfortunately there wasn't any gas stations, I was able to drive another 8/10 of mile before having to turn onto a residential side street where the car died. The wife and I pushed it the last few feet to get it out of the street. We had a bit of luck as one the homes had a yard crew cutting its grass. I paid a guy $5 for a half gallon of gas, enough to get us to the gas station just a couple of blocks away. Didn't have any problem pouring it in or with the car starting. I was really surprised by it only going 2 miles on HV battery.. I was under impression models with EV mode are able to go 5-7 miles using same battery.

    Odd, I had just checked the fuel 40 miles earlier and it was showing 2 segments. I equated those to roughly 2 gallons remaining.
    We never heard any warning, certainly nothing like the Reverse klaxon that goes off when in reverse, or seat belt warning alarm.
    We never figured out why we ran out of gas considering we averaged 40mpg and the tank was full when we left.. all segments (10) were showing on the display.

    We also notice our tire pressure indicator kept cycling on and off through out our trip, even though pressure was correct.


     
  7. hiremichaelreid

    hiremichaelreid New Member

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    1-2 miles is normal. Prius could go farther if HV battery started fully charged and ended completely discharged, but that would massively shorten battery life.
     
  8. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Wonderful story! Can you imagine what would have happened in any other car?

    To get maximum distance on your battery charge, minimize all loads and try to get your speed down to 20 mph without braking.

    Thanks for sharing!

    Bob Wilson

    BTW, you may want to 'clear the codes' in your control computers that recorded this out of fuel situation. Patrick's recommended approach is to disconnect the auxiliary battery negative cable at the car frame for about 10 minutes and then reconnect it. You may need to re-adjust the driver side window roll-down system.
     
  9. richard schumacher

    richard schumacher shortbus driver

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    If only there were some indicating device on the dash to show when fuel was running low! Damn you, Toyota! Damn you!!!

    Uhh... how do you know that all the tire pressures were correct during the drive? What are they now?
     
  10. icarus

    icarus Senior Member

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    With a range of ~500 miles, are we suffering a shortage of gas stations?

    Driving from Winnemucca to Tonapahm, the idea of trying to maximize the range sounds kinda dumb. No where else in N.America is more than ~50miles from some sort of gas. It just sounds kinda dumb. We drive all over the west, and somewhere within 500 miles someone needs to go the bathroom!

    Stop and get gas at the same time!

    Icarus
     
  11. Prius77094

    Prius77094 New Member

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    When I get down to three bars, I start looking for a gas station. It is not worth risking a dead car, or the minor inconvenience of having to reset stuff just because I ran out of gas. That would make an ironic picture, a person holding up a gas can on the side of a busy road, and the person out of gas is driving...a Prius!
     
  12. Scruge

    Scruge New Member

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    We've only had our Prius since Nov 07 and its got 2500 miles on it.. The wife uses it as a grocery getter and normally tops off the tank at half a tank or less. The trip was the first time we had ever taken the fuel gauge below half tank.. so we weren't sure what to expect. I certainly didn't expect to run out of gas with only 360 miles on a full tank. I also was expecting the warning to be a little more noticeable, like a message light or alarm, same as my other vehicles. After-all the reverse klaxon is loud enough to drown out the screams of a small child you might be backing over. From what I've learned we are in the survey's less than 5 miles group for our warning. Still can't figure out how one can average 40 mpg and only go 360 miles on 11gallons.. must be the new math they're teaching now.

    The first time the tire pressure came on I exited and checked the pressure with a gauge. While checking, the light turned off. About 15 minutes back into the drive the light turned on again. This time we noticed it would flash for about a minute before staying lit. According to manual, it meant there was a problem with sensor rather than tire pressure. We noticed through out our trip the indicator would periodically reset itself.
     
  13. richard schumacher

    richard schumacher shortbus driver

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    True, the silently flashing pip on the gauge is less than blatant.

    With a variable-capacity bladder inside the tank the capacity is usually less than 11 gallons of fuel. More to the point, you can't be certain how much fuel it contains now. This makes it dangerous to project the remaining driving range. When you ran out you must have actually started with about nine gallons.

    That intermittent tire pressure warning is a problem for warranty diagnosis and repair.
     
  14. Scruge

    Scruge New Member

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    Yep, I agree, we certainly didn't have any trouble noticing the tire pressure indicator every time it cycled. I personally don't think the flashing "E" started until the car ran out of fuel. Or because we had our headlights on, the flashing E was dimmed with the night settings making it less apparent.

    Considering all the hype about voiding warranty and frying the HV battery it seems a little more attention could have been given to the Fuel monitoring and annunciation system.
    Variable volume fuel tank, inaccurate level detection, and poor annunciation will assuredly lead to more people running out of gas.
     
  15. dwreed3rd

    dwreed3rd New Member

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    Just reminiscing:
    Does anyone remember the 1962 and earlier VW Beetles. They didn't have a gas gauge. They had a lever under the dash. When you ran out of gas you turned the lever which switched to an auxillary tank which gave you several more gallons. Not sure of the actual mechanics, you only had one filler tube. filled it though the spare tire in the front of the trunk. Wow! sweet memories. I had a 1962 1/2 model which added the gauge but still had the partitioned tank. Even though I watched the gauge, you could get caught between gas stations. I remember in 1977 driving from Harrisburg, Pa. to Atlanta, GA, during the fuel shortage, not in the VW though. It wasn't always easy to find a station open with gas. Many stations that were open had rationing and there were long lines. It would have been nice to know you had the backup fuel to get you to the next station; and I really don't like carrying cans of fuel in the car on a regular basis. I haven't found one that doesn't leak at least some fumes into you car. I know it's not an option, just reminiscing. But sometimes old ideas worked well.
    By the way, we try to never let it go below 1/4 tank in any of our cars. Havent run out of gas in years. Many of the late model cars can be difficult and/or expensive to restart after running out of gas. You just don't pop off the air cleaner, pour in a little gas, and crank 'er up anymore. And, besides, in today's market, if you wait until tommorow to fill up, the price will pobably have gone up.
    Hope I didn't bore you too much.
     
  16. kevgrn114

    kevgrn114 New Member

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    I ran out of gas when I first got my prius in 2001. I had never driven anything with a bladder. The gas guage seemed to go down exponentially, small decreases when it was full and faster and faster as it went down. At the time my drive was 60 miles one way. When the engine did die the warning lights came on the dash. the engine never tried to kick over again so I'm assuming that toyota would make the fuel pump not engage. But I would also assume that if driving on the battery is so bad for it that toyota would make the car unable to drive on just the battery if the gas engine "logs out" of the hybrid state. Also someone mentioned something about driving onthe battery till it died then restarting again and driving further on the battery. Does this mean that the car cuts itself off before the battery drains to fatal battery degredation?

    I have never run out of gas since then but have run down to the blinking light more times than I can count, I just go to the nearest station which is always pretty close as I am just driving 23 miles between Dallas and Fort Worth.

    I've never been a huga fan of the gas gauge accuracy but from what I understand the bladder is safer since there are fewer fume accumulations in the tank, so the trade off is ok I suppose.
     
  17. kevgrn114

    kevgrn114 New Member

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    Oh yeah.. in regards to the reserve tank on the old VW's, that is the same as my motorcycle has. I have no feul gage onthe motorcycle, just a reserve switch. All of the gas is in the same tank, there are no partitions. It is simply two different fuel hoses, one higher and one lower. in regular mode the gas is fed from the tank via the higher hose. When the level drops below the higher hose then the engine sputters and you have to flip the switch to reserve mode which then simply feeds the gas from the lower fuel line. Nice and simple.

    That being said, my motorcycle is carburated. the fuel injected motorcycles have a gas gauge on them because running out of fuel on an injected model is bad for the injectors.
     
  18. berinker

    berinker New Member

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    Ha, ha!!!
    You have not seen the
    Western deserts.
    Bud
     
  19. alanh

    alanh Active Member

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    There are a handful of places, but it's not common. There's 106 mile gap on I-70 between Salina and Green River, UT. You can just tank up in those cases.
     
  20. archae86

    archae86 Member

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    I think they usually tell you with a sign if it will be more than 50 miles or so on a major road. But 30 is nothing at all unusual. So folks who get used to waiting for the flashing warning would learn better out here.

    True story--we took delivery on our Prius in Roswell (yes, that Roswell) although we live in Albuquerque NM. We drove down by what passes for major roads out here, but deliberately took the road less travelled by for the trip back. We averaged passing one cattle ranch about every five miles, and something like fifty miles of it was gravel, with some of the paved part not really better.

    We found out what one of the Prius reviewers meant by "drumming". The road sometimes excited a bodywork resonance at about 28 mph. It was easy to get out of by going a little faster or slower. In two years of driving on paved roads, we have not heard it again.