Fuel Tank

No, you aren't the only one. That's the way it works with the U.S. version of the Prius. The manual states 11.9 gallons for the gross capacity of the tank. The usable capacity is closer to 10, and variation caused by the bladder inside the tank makes it hard to know exactly how much usable fuel you have. I usually put about 8.5 gallons in mine on each fill, but I try not to run it down too close to empty. It's just not worth pushing it if it's not necessary. If you want a lot more information, search on the term "guess gauge".

Tom

 

<div class='quotetop'>QUOTE(pat2762 @ Nov 19 2007, 10:45 PM) [snapback]541788[/snapback]</div>

At 50 mpg you can go 500 miles on a tank, but you might have to coast to the edge of the road when you run out. Some people are hyper-milers, and work very hard to get extremely high mileage. Others like to push a tank to its very limit. The ones getting 600 - 1000 miles on a tank are doing both. I don't see the merit in pushing a tank to its limit, but to each his own.

Tom

 

I had a similar issue the other day, got really cold here, well cold for San Francisco, went to CostCo, left the store and went to fill up since I only had 2 bars left, I had driven close to 400 miles at this point. I put gas in, and the thing maxes at about 2.7 gallons! Now I know I was hypermiling or anything. I tried a couple more re-adjustments and to put more gas in but nada, I attributed it to a cold bladder that wasn't stretching as it should.

Now the kicker is my fuel gauge stayed at 2 bars! *Grrrrr* and did so for the next hundred + miles!

There definitely is some squirrelly happenings that can occur with that bladder.

 

Very few accurate fuel gauges out there. I have learned to trust my trip odometer, (assuming the Prius has one) reseting it at ea. fill up. Once a reliable mpg can be established, I would go by the mileage.

If the tank is a comfortable 10 gal usable, and your comfortable with 50 mpg, that would be 500 mile range, I would fill up @ 400 miles, and work it from there. This would give you a 2 gal reserve. In winter, I would figure closer to 40 mpg. At 10 gal is 400 miles, fill up @ 350, should give you at least a 50 miles reserve.

 

I don't like pushing it but I've been putting off a trip to the gas station with this virus shutdown. Today, for the first time ever, I actually saw the blinking last pip indicating running out of gas was imminent. Ten downhill miles later the car only took 9.179 gallons(US).

The rubber bladder is very inconsistent. Looking at the ledger book I keep in the glove compartment I see I have put more fuel in the tank about a dozen times and, as I said, never had the blinking light before. The most it ever took was 10.004 gallons and it was still displaying two pips on the gauge.

That's why I almost always try to fill it up when it's convenient once the gauge displays two pips left in the tank.

 

Nothing worse than inconsistent bladders!