In the last month, I've been getting less miles per fill up. Previously the gas light would hit 1 bar around 400 miles. Now its hitting 1 bar around 350-360 miles. But when I fill up, I only fill up about 8 gallons so I haven't lost any gas mileage. It feels as if the tank shrunk on me. Anyone else experience this?
Yes! Exactly what you stated. The internal bladder in the fuel tank shrinks a bit or stiffens when the temperatures drop this time of year. Therefore, your system holds a bit less fuel. I've not heard of any experiments to try and precisely correlate volume lost to ambient temps but over the last 8 winters, my sense of the thing in my Gen 2 is that I'm losing about a gallon storage volume at a 40-50 degree F. drop from our normal summertime highs of 95-100 here in Texas to wintertime lows of 30-45.
Yes all the gen2 (2004-2009) in North America have flexible bladder which gets less flexible in cold weather, try afternoon fill ups.
Thanks, I just updated my profile. I do have a gen 2. sorry for the confusion and thanks for the explanation.
Besides the bladder stiffen up, you probably need to re-calibrate the fuel gauge. Fuel Gauge Calibration Instructions | PriusChat
