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Hi All:

___I will be filling up in a few hours but I am wondering approximately how many gallons are left when the last pip starts to blink as well as when the pips disappear? She is blinking right now but just to give me an approximate range when I actually take her out to those limits later on this week after a fresh fill?

___Thanks in advance.

___Good Luck

___Wayne

>>how far one can drive beyond last pip

You? Probably 300-400 miles :D

Hi Wayne, I drive way to many miles (we bought our prius on march 15th and have almost 10000 miles on it already) so I fill up alot. I have gone as far as 30 miles on the blinking pip, but usually after about 10-15 I head for the pump. I have gotton as much as 10.8 gallons in after running it down that far.

madman

Hi Sledge:

___Maybe if someone dropped me off at the International Space Station for the free Glide home ... maybe :)

___Madman, thanks for the reply. This is a first gen 2002 Prius (second gen for those from Japan ;)). I am already 60 miles into the blinking last pip but have to fill for an SG-II calibration today. I would like to take her down all the way to no-fuel but will not have the time for an on-the-road fillup. The next tank should allow me to find those limits however? I would like to have an idea + or – 10 to 15 miles as to when she will go into fuel starve but I do not have even the faintest idea as to how much fuel is left at the first signs of the blinking last pip or after the last pip disappears?

___Good Luck and thanks in advance.

___Wayne

I have not exceeded 30 miles on 'flashing E' in 2001 Prius. Never a fuel exhaustion either, because they seem worth avoiding.

Others may have reported 100 miles or so. Yesterday I had a 10.911 gallon refill in the 'not yet flashing' mode. So depending on which capacity estimate one uses, there might have been 50-70-whatever miles of range left.

The pesky bladder makes this a difficult matter to pin down, I think. There is also a procedure for 'fuel gauge inclinometer reset', which says to me there is room for substantial variability among vehicles.

DAS

Wayne,

With the issues with the bladder making exact measurements at any point an impossibility consider the tank as being 9.5 gallons. This leans to the side of caution but there have been reports of some folks only being able to load 9.2 gallons into the bladder, not in times of extreme weather, but in times of rapidly changing weather.

Despite any hypermiling efforts I would count your static MPG as 40, again leaning to the side of caution.

There are 8 pips on the fuel gauge, so 9.5 / 8 = ~1.2 gallons per pip. 1.2 * 40 = 48 miles on the last pip. Err even further on the side of caution and allow yourself just half of the last pip, making your absolute fill-up time roughly 25 miles into the last pip.

This way you'll never find yourself running out of fuel despite any issues with the fuel bladder on your worst hypermiling day.

Hi Doug:

___So you believe there may be ~ 100 miles as soon as the last pip starts blinking at 50 or so mpg? That means 2 gallons which is what I will hang my hat on once she begins flashing late into the next tank. The bladder issue is moot at that level so hopefully the Fuel Level Sending unit is Hypermiler friendly in the case of Cheryl’s Prius I ;)

___Brian, I have only filled a Prius I (yesterday) and II (Prius Marathon Attempt) once each and both times, the bladder issue really did not or should I say had not reared its ugly head? Early/Late Summer fills for both respectively however.

http://www.cleanmpg.com/photos/data/500/Prius_II_Marathon_Attempt_-_Fillup_I.jpg
Prius Marathon Attempt - right to the lip.

___Yesterday’s fill allowed a 12.1 gallon total in the 11.9 gallon rated cap tank so I am hoping there is an almost 13.0 gallon total cap in her.

___Thanks for the replies!

___Good Luck

___Wayne

I usually monitor my mileage by following the pips and miles travelled in the NHW10, so I can probably answer this. I presume the NHW11 is the same. According to the NHW10 manual there is 7L left when the E light comes with one pip left. On average on only 4 attempts, I have seen only 2.7L (calculated from average mpg) until the no pips left comes on. So there should be a further 4.3L but I havenot pushed it.
Anyway as you know the pips are non-linear, 9-8=3.95L, 8-7= 5.15L, 7-6=5.15L, 6-5=4.75L, 5-4=4.95L, 4-3=4.5L, 3-2=4.27L, 2-1 3.7L, 1-0=2.7L. (estimated from 20tanks)Monitoring the miles travelled for 10-9 pip usually tells me whether there is underfill.

Good Luck
Andrew

Wayne,

Be very careful about taking the Prius I to a no fuel condition. The battery management system in the NHW11 does not protect the hybrid battery from run down as the NHW20 does. There have been instances of Prius I hybrid battery replacements due to running out of gas and then using EV until the battery is exhausted.

Wayne

Yeah, but some of those "replacements" were because dealer
techs had no clue how to recharge the HV battery. Sure,
deep discharge isn't particularly good for the cells, but
ONE excursion down past 20% or so isn't going to kill them.
There's way too much mythology floating around about this.
.
_H*

Maybe it's a bit silly, but why not carry around a quart/gallon of fuel and find out exactly how far that last blip will take you?

Hi Wayne and Hobbit:

___I do not plan on driving any distance beyond Fuel Starve other then the coast down but I would like to guesstimate the range so I am not driving through the Kennedy junction (I-90/94 junction here in Chicago) or past the Ike/Tri-State merge (I-290/294) when it occurs ;) It will more then likely happen on the highway and I will pull her over into a maintenance lane for a container fill-up just as we have done in past Marathons.

___John, I will have a gas can but I prefer not to be driving around with a 2-gallon container of liquid dynamite for 2 days when I can limit it to maybe a half hour or something :angel:

http://www.cleanmpg.com/photos/data/530/one_gallon_to_get_to_station.jpg
Randall filling up at the Insight Marathon - Fuel Starve location.

___Good Luck

___Wayne

Fair enough Wayne. Sometimes one has to be a scientist to be scientific. ;)