Set out today with about 2/3 of a tank or so averaging my usual 35mpg or so. While travelling, I noticed the fuel gauge was now showing a full tank. I thought "wow" thats the secret, the Prius will manufacturer its own gas if you give it enough time. My problem was actually buying gas!. Well, we got to our destination and a few hours later when I turned the car on, it was still showing full! On the trip home though, the gauge fell fairly quickly and I am now a little over half. When it first happened, I thought turning the car off and on would reset it but it took awhile on the way back for it to start falling. Does this sound like a mechanical or electronic issue?
