That's exactly another reason why we should never try to squeeze every last mile out of the empty gas tank. The manufacturers deliberately calibrate the fuel guage to be negative on purpose. You'll notice how when the fuel guage is below half a tank, it seems to disappear very quickly. When I have only 1 bar left on my S2000, I can only stuff 10.2 gallons in at the most. The same goes for most vehicles out there. In my old 95 Taurus SHO and 99 Taurus SHO, when it was down to a 1/4 tank on the guage, I still had 5-6 gallons left in the fuel tank. On my dad's Crown Vic, when the fuel gauge is down to one bar, same thing it's still got at least 5-6 gallons left.

 

I agree that there are about 2.6 gal left when loight comes on. Question is, how much of that 2.6 gal is USABLE. My 88 Prelude would quit running with 1.4 gal left in the tank. The pump won't pick up the last drop so some of the capacity is unusable. Has anybody run out of gas and know how much it took to fill up?

 

That's generally the case on most cars. I have to say that i've suffered the embarrassment of running out of gas in my old 97 Ford Taurus with the Duratec motor which has a 16.8 gallon fuel tank, and after I rolled it into the gas station which was only 150feet away, I was only able to stuff 15.7 gallons into it at the most no matter how hard I tried to top off. That's right on par since Ford claimed in that vehicle, that about 16.0 gallons of the 16.8 gallon fuel tank was usable.

 

I do a lot of driving and so buy a lot of gas. My S gets every bit of 27+ mpg, only slightly less in heavy traffic (the only time a 6-speed really sucks!). I've gotten over 320 mi. between fills and never more than 11.8 gal to fill. Don't want to find out real capacity.

 

Wow, 11.8 gallons, and I thought I was on vapor when I put in 11.5!!
Did get about 50 miles once when the fuel light and no bars showed... but as said elsewhere, it was exciting!