This article is from the Gasoline FAQ, by Bruce Hamilton with numerous contributions by others.
* You forgot to refill it.
* Your friendly neighbourhood thief "borrowed" the gasoline - the unfriendly
one took the vehicle.
* The fuel tank leaked.
* Your darling child/wife/husband/partner/mother/father used the car.
* The most likely reason is that your local garage switched to an oxygenated
gasoline, and the engine management system compensated for the oxygen
content, causing the fuel consumption to increase ( although the effect on
well tuned engines is only 2-4% ).
 
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