!!Fuel Bladder Frustrating Me!!

With a nine gallon fill, you should have just over a gallon left in the tank before filling.

The NA Gen II Prius fuel tank is rated at 11.9 gallons gross. The usable amount is closer to 10. You may get 11 when the stars align and the weather is warm, but don't count on it.

Tom

 

i've never gotten more than 10 gallons in, but it lasts a month so i don't think about it i'm just not sure you can get much more in than that.

 

mikesarebetter, you are in South Dakota, correct?

During the cold winter months, the Gen2 Prius fuel bladder will hold less fuel, because the cold weather makes the fuel bladder stiff and unable to expand as readily as during hotter weather.

Your situation sounds normal to me. Prius drivers elsewhere also experience what you saw during cold weather (less fuel capacity in the Gen2 bladder and lower MPGs).

 

You are achieving the same normal results that many of us here are getting! I have never put more than 9 gallons in EVER! I fill up with 2 pips to go, have never run out of gas, which is a bad thing Egon!
Mileage will go down in the winter, up in summer, you are right on track!

 

And you can't "calibrate" the fuel gauge. It's a computer controlled device. I've never heard of anyone "hacking" it.

 

In winter I get 8+ gals in summer 9+.
Also some gas pumps fill up more for some reason.
Sometimes you get 40 then a 60 MPG buts its really 50.

 

It is possible that the fuel system inclinometers need to be reset.

Here is the procedure that has been posted in other threads:

Bear68
Senior Member

Easter Egg Time.... Anybody wanna reset the fuel gauge inclination
sensor? Make sure your fuel level is somewhere between 1/4 and 3/4, and
temp should be about 70-90 F.

Step 1: PARK ON A LEVEL SURFACE!!!! If you are on a slope you will reset
the sensor to an incorrect level!!
Step 2: Press the ODO/trip button to turn the odometer to trip A
Step 3: Turn off the ignition and set the parking brake.
Step 4: DO NOT STEP ON THE BRAKE PEDAL! AT ALL! IT ISN"T NEEDED FOR
THIS PROCEDURE!!
Step 5: Press and hold the ODO/trip button and press the Power button
twice.
Step 6: Release and press the ODO/trip button three times
Release-Press-Release-Press-Release-Press and HOLD.

The Odometer on the combo meter should now be showing the normal
mileage, as you hold the ODO/trip button down, the reading should change.
Something along the lines of 650D0 or similar. The actual figures don't really
matter.

Step 7: Release and press the ODO/trip botton once more and HOLD it in.
The figure will change again. This time, only ONE digit will change.
650D0>65010 as an example.

Don't be afraid to try it. Even if it doesn't work, you won't goof anything up.
Try, try again. It sometimes takes a half dozen attempts before you get it
work right the first couple of times you do it. This only needs to be done
once in a while. I would recommend once every ten tanks or so. I usually
only do it when a customer has a fuel gauge issue. [Emphasis added.]

Takes a bit of practice but it resets the ECU to try to be more accurate in
it's estimation of your actual fuel level.

GOOD LUCK!!

 

I do the same thing. 2 pips.

 

My computer mpg rarely matches my Fuelly calculation. Sometimes it is spot on though. If I let the fuel level get low enough to where I get a low fuel warning on the MFD, it will take 9.2 or so gallons to fill it.

I love being able to drive all week and then put less than 8 gallons in the tank, only happens when I fill at 1-2 pips though.

 

Same thing here in South Jersey, Cold weather, bladder stiff = more stops at the station. My problem is I only need to get gas every 3 weeks or so. Once I heard a slight beep and my last pip was blinking! Geez, that will put you into hyper mile driving mode fast. Fortunately there is a gas station every 3 or 4 miles around here and there was no problem.