Fickle Fuel Gauge or Shrinking Fuel Tank?

When it started to shudder I knew I was running on vapors. With precious little energy left to get to a gas station in the Nevada desert, I let my Prius slow gradually from its 65mph cruise. My display read 478 miles, 47.1 mpg.

The mental battle had begun way back, when Add Fuel came on somwhere over the Sierra Nevada Mountains, just 400 miles after I had topped the tank. I never had a car with a reliable fuel gauge, but I always knew the tank capacity of any car I drove. 11.7 gallons for the 2004 Prius. The fuel computer had proven itself over 8000 miles of driving -- I could make it to 500 miles with a gallon's reserve left over. It would have been insane to add fuel now.

The engine sputtered for another moment before giving out completely. Amidst the silence of the cabin I was told in big, threatening, red letters there was a "Problem!". Even now, reporting in its methodical, measured way, my Prius car was not jumping to any conclusion that I had afterall run out of fuel.

Just two bars on the battery! Where did the juice go? I just came out of a long climb over the Sierra Nevada Mountains. Was it making room for a expected descent?

No descent was to be had. I had slowed way below the flow of traffic. Instead of using my flashers the only thing that occured to me was to take the break down lane. Alas, the lane was too narrow forcing my left side to vibrate over the bumps. I figured it was costing me too much energy and swerved dangerously back onto the driving lane.

I took my first exit with only a vague belief I saw a sign for gas. Just as I took the turn, I saw the gas sign for the NEXT exit. Oh well, would never have made that far anyway.

Incredibly, with what was left of my coasting speed, a single bar of energy got me up a torturous, under-construction off-ramp, over an overhead pass, and accelerated back from a red light stop to arrive at the Union 76. The display now read 480 miles.

I checked that the gas station was indeed level as the eye could tell. My Prius car took in 10.035 gallons from empty. Indeed I had the shrunken fuel bladder. It was 55 degrees, not freezing cold but colder than last summer -- when Add Fuel came on back then I could put in 10 gallons.

Yet one more way in which this car isn't like any other. I won't ignore the fuel gauge again, at least not in my Prius car.