Reserve Tank

You can bounce back from that. Just record the gas put in, and the distance travelled. Then next time you refuel, fill the regular way, again record distance travelled, and gas put in. Add the 2 gas amounts, the 2 distances travelled, and do the mpg calc from the totals.

 

When "flash" begins, there is 2.1 gallons remaining until our 2010 Prius runs out of gas. But I am amused that someone would call it "a 2-gallon reserve tank."

Bob Wilson

 

I would be inclined to believe the op misinterpreted the phrase "there is 2 gallons of reserve in the tank", not that there is a separate reserve tank.

 

While that seems like the most likely explanation, I definitely could believe that the misinterpretation occurred somewhere else, up the supply chain.

 

Yeah, salespeople can say the most boneheaded things sometimes.

SCH-I535

 

We are making too much of ,,, how much does it hold , to figure MPG
,,,, let's see I put in 5 gallons of gas , I drove 250 miles since I had filled up ,,,, divide it out
I got 50 mpg doesn't matter , so the size of the tank means nothing

 

You can use a Scanguage II and set it up to give a fairly exact estimate of the exact gallons of fuel remaining in your tank. As you refuel you tell it how many gallons you have added and it adjusts its fuel consumption estimates by a "fudge factor" to bring estimated and actual fuel consumption into the closest possible agreement. The exact fuel remaining estimates are important if you must stretch your range as far as possible, for example if you are driving in the upper Yukon or other deserted areas.
Cheers!

 

Math counts, People.

 

My experience:

From the moment my last pip started flashing up until i ran totally dry, i calculated exactly 10 litres. This based on the actually fillup vs kilometres travelled.

Google converted 10 litres to 2.64 gallons
.
.
.

 

It won't affect your mileage calculations as long as you are measuring the amount of gas burned over the distance covered with it. For example, the amount you put in the tank should be compared to the number of miles since your last fill. If you ran it to the last drop, you'd have more miles than if you filled it as soon as it showed "empty."

Zeroing the trip-meter at the last fill and filling the tank to where it automatically shuts off each time should give you the most accurate mileage results.

 

So, what's the most amount of fuel anyone has put into their Prius at a fillup? I've only had mine a month and the most I've pumped is just under 9.4 gallons. I think the low warning beep and flashing bar come at around 9.1 gallons used on mine. Has anyone gotten 11.4 into their tank. It would be nice to know for those long distance trips that I could go another 90 or 100 miles before I absolutely needed to stop. Even 10.9 gallons would get me another 65-75 miles or so past the point where I've been filling up.

 

The stated capacity is 45 liter which is 11.9 US gallon or 9.9 imperial gallons (for the UK or commonwealth). The most I've put into it was 44.03 liter which is 11.6 US gallon. In my experience when the last bar starts flashing there is about 9-9.5 liter (2.4-2.5 US gallon) left.
This is a european spec Prius but I doubt the gas tank is different.
I regularly drive 200 km (125 miles) with the flashing bar.

 

The last thing I'd want to try on a long trip is running a tank near-dry.

 

Maybe they wanted to take a hike. Me, I am more bound by the range of my bladder than my gas tank.

 

In the 800mile club thread, the maximum fill up was a little over 50litres (above 13 gallons). This from bone dry to overfilled gas visible up-to-the-filler-lip refill.

Don't try doing that unless you are sure your going for a long drive and will immediately consume the overfill.

 

Thanks, that's exactly the kind of experience I was looking for. I understand people's anxiety over running out of gas but these cars get such good mileage it seems silly to fill up when you still have a cushion of 100+ miles. From where I live in Atlanta that's enough to get all the way to Chattanooga. So, I'd feel very confident about leaving 1.5 gallon in the tank and filling it when it needs about 10.4 gallons or about 1.3 gallons ( let's call it 60 miles) after the fuel bar starts to flash. That would still give me a 60 mile cushion before empty.

 

I also drive around 200 km with the last pip flashing. But never assume you always can.

You could be averaging 3.7liters/100km (63.5mpg) for most of the tank, but find yourself going up a steep incline for the last portion of the tank doing only 5liters/100km (47mpg).

This actually happened to me when i was trying to make the 700mile club. I ended up empty at around 690miles due to the incline in the last leg of my trip.

 

To quote a British General:
"You are a better man than I , Gunga Din!"

But two follow-on questions:
Are you truly winging it with the standard gas gauge, or do you augment that with something more precise like a Scangauge II ?
Do you have a spouse nagging at you for the entire 2+ hours it takes you to drive the 125 miles with the last pip flashing? (Gunga Din was not, as I recall, married.)
Cheers!

 

Those of us locked in connubial bliss are involved in a two-body problem and are also limited by the "bladder range" of DW !!

 

1: I reset trip B the moment the beep goes off and the last bar goes flashing, just to see how far I've driven. No Scangauge.
2: No nagging because I am like Gunga Din (had to look up who he was )

What's more: on my usual commute of 30 km I'm passing 4 gas stations. So whenever I feel the urge to fill up I can always do so (or when I have to walk it's not far). There are no long desert or mountain stretches here. I was caught in the mountains once when the last pip started flashing and I chickened out after about 50 km. Ended up filling only 37,84 liter so I could have gone 150 km more.