Driving Past The Add More Fuel Beep

[KAR IDEA]

Sooooooo, I grew tired of playing the "Add Fuel" game after driving the car for nearly two years, and adding fuel as soon as the car told me to.

One day 8 tanks ago, I decided to drive 20 miles further and the car took 10.1 gallons. Then 7 tanks ago I drove 30 miles further and the car took 10.6 gallons. Then 6 tanks ago I pushed it to 40 and the car took 10.9 gallons. Then 5 tanks ago I drove 50 miles further and the car took 10.8 gallons. I kept it at 40 to 50 miles beyond the add fuel warning for the next 3 tanks, and the car took between 10 and 11 gallons each time.

I just filled it today and pushed this last tank/bladder to 60 miles further. The car took 11.2 gallons.

If this is information is useful to you, excellent! If it's not, that's fine too. My little experiment in a nutshell, has proven to me anyway, that I am safe driving at maximum, 50 to 60 miles past my add fuel warning...something to keep in mind when on a lonely road with no gas stations in sight. : )

[JimboK]

Judging from reports in the forums, there is wide variability in how long the car will run after the beep. Good for you so far, but next time it might be only 4 to 5 miles. If I'm low on fuel, I refuel before I hit a lonely road where there's likely to be no gas in sight. Why push your luck??

[toxicity]

I realize that it is important to get a zero-tank in order to have fuel economy measurements that are accurate; however, driving when the tank is that low is extremely risky.

What I would recommended instead, is when you get the add fuel warning, pull into a gas station. Then, with the parking brake on, press on the gas pedal and brake pedal, and run the tank dry.

That way, before any of the serious stuff that happens when the tank is dry for more than, I don't know, a minute, begins to happen; you can fill it up right then and there, and you will be as close as you can possibly be to getting a fillup from zero.

[Shawn Clark]

Originally Posted by KAR IDEA

Sooooooo, I grew tired of playing the "Add Fuel" game after driving the car for nearly two years, and adding fuel as soon as the car told me to.

One day 8 tanks ago, I decided to drive 20 miles further and the car took 10.1 gallons. Then 7 tanks ago I drove 30 miles further and the car took 10.6 gallons. Then 6 tanks ago I pushed it to 40 and the car took 10.9 gallons. Then 5 tanks ago I drove 50 miles further and the car took 10.8 gallons. I kept it at 40 to 50 miles beyond the add fuel warning for the next 3 tanks, and the car took between 10 and 11 gallons each time.

I just filled it today and pushed this last tank/bladder to 60 miles further. The car took 11.2 gallons.

If this is information is useful to you, excellent! If it's not, that's fine too. My little experiment in a nutshell, has proven to me anyway, that I am safe driving at maximum, 50 to 60 miles past my add fuel warning...something to keep in mind when on a lonely road with no gas stations in sight. : )

The blinking pip is supposed to start at ~12% indicated per a post from Evan a few months ago, roughly 1/8th tank. Your results appear consistent with that.

In a normal car with analog gauge the empty line is at about 1/8th (looking at the scale and examining gallons added over many years) and the idiot light starts somewhere around then. I'm accustomed to running down to the equivalent of 5% of rated capacity on other cars, pushing it just as you describe--never had an out of gas situation that way...only at 25% indicated. It is MUCH easier in other vehicles since they don't have pips and the needle keeps going lower...while with the Prius the "needle" effectively disappears at 1/8th tank. Would love a digital gauge that showed something useful like actual percent. Dumbing the thing down is unhelpful.

Unfortunately the Prius has a bladder and complex tank gauge plus complex vent system that make its indicated tank level less reliable than other vehicles I've owned. So while applaud you for testing and reporting this, I'm not planning to push mine...at least not any time that I'm concerned about what happens if I run out of gas.

[DaveinOlyWA]

Originally Posted by KAR IDEA

Sooooooo, I grew tired of playing the "Add Fuel" game after driving the car for nearly two years, and adding fuel as soon as the car told me to.

One day 8 tanks ago, I decided to drive 20 miles further and the car took 10.1 gallons. Then 7 tanks ago I drove 30 miles further and the car took 10.6 gallons. Then 6 tanks ago I pushed it to 40 and the car took 10.9 gallons. Then 5 tanks ago I drove 50 miles further and the car took 10.8 gallons. I kept it at 40 to 50 miles beyond the add fuel warning for the next 3 tanks, and the car took between 10 and 11 gallons each time.

I just filled it today and pushed this last tank/bladder to 60 miles further. The car took 11.2 gallons.

If this is information is useful to you, excellent! If it's not, that's fine too. My little experiment in a nutshell, has proven to me anyway, that I am safe driving at maximum, 50 to 60 miles past my add fuel warning...something to keep in mind when on a lonely road with no gas stations in sight. : )

i went 120 miles past the blinking bar and 60 miles past zero on the DTE (distance to empty) on my 2010

Originally Posted by JimboK

Judging from reports in the forums, there is wide variability in how long the car will run after the beep. Good for you so far, but next time it might be only 4 to 5 miles. If I'm low on fuel, I refuel before I hit a lonely road where there's likely to be no gas in sight. Why push your luck??

if using luck, i would agree. better to know your car and driving habits. using the fuel amount you put in and the mpg's on the current tank is a better way of estimating how far you can go (assuming no one siphoned u!!)

Originally Posted by toxicity

I realize that it is important to get a zero-tank in order to have fuel economy measurements that are accurate; however, driving when the tank is that low is extremely risky.

and exactly why is this important?

Originally Posted by toxicity

What I would recommended instead, is when you get the add fuel warning, pull into a gas station. Then, with the parking brake on, press on the gas pedal and brake pedal, and run the tank dry.

forget the answer to the first question...after this line, i will pass on any advice you wish to offer

Originally Posted by Shawn Clark

The blinking pip is supposed to start at ~12% indicated per a post from Evan a few months ago, roughly 1/8th tank. Your results appear consistent with that.

.

this is correct as verified by CANVIEW where the tank volume is display in percentage, but the graduations are actually at 2.5 % intervals so tank will measure

100
97
95
92
90 etc...

[2009Prius]

Just a reminder that 2010 does not have the bladder problem that previous model years suffer from.

[TonyPSchaefer]

Originally Posted by KAR IDEA

One day 8 tanks ago, I decided to drive 20 miles further and the car took 10.1 gallons.
Then 7 tanks ago I drove 30 miles further and the car took 10.6 gallons.
Then 6 tanks ago I pushed it to 40 and the car took 10.9 gallons.
Then 5 tanks ago I drove 50 miles further and the car took 10.8 gallons.
I kept it at 40 to 50 miles beyond the add fuel warning for the next 3 tanks, and the car took between 10 and 11 gallons each time.

Using this information, solve for x.

I'm sorry, what were we talking about?

[toxicity]

Originally Posted by DaveinOlyWA

and exactly why is this important?

It is important because gauging accuracy based on driving 500 miles with 8 gallons of gas versus 10 gallons of gas will lead to different results with either amount. One is more accurate. Don't you think?

Originally Posted by DaveinOlyWA

forget the answer to the first question...after this line, i will pass on any advice you wish to offer

Wow....would you maybe like to correct me with some helpful advice, instead of acting like a douche? Seriously.

[richard schumacher]

Everyone needs a hobby, but surely there's something more fun than deliberately running out of gas.

[DaveinOlyWA]

Originally Posted by toxicity

It is important because gauging accuracy based on driving 500 miles with 8 gallons of gas versus 10 gallons of gas will lead to different results with either amount. One is more accurate. Don't you think?



Wow....would you maybe like to correct me with some helpful advice, instead of acting like a douche? Seriously.

Originally Posted by toxicity
What I would recommended instead, is when you get the add fuel warning, pull into a gas station. Then, with the parking brake on, press on the gas pedal and brake pedal, and run the tank dry.

oh sorry, i over reacted. i hadnt realized you meant that as a joke

if you look at the two quoted statements. in one you suggest that running a tank dry (hopefully you meant just real low) to get "better and more accurate" tank data

then right after that, you said wait until the last pip starts blinking.... then tie the car down in place and run the car until it runs out of gas as you watch your mpg's slowly drop to 30 something mpg.