Toyota 2008 Prius Quick Reference Manual page 110

Closing the fuel tank cap
n Fuel types
Use unleaded gasoline. (87 Octane Rating [Research Octane Number 91] or
higher)
Fuel tank capacity
n
Approximately 11.9 gal. (45 L, 9.9 Imp. gal.)
PRIUS_U_(L/O_0802)
After refueling, turn the fuel tank
cap clockwise until you hear a
click. The cap will revolve slightly
in the opposite direction once
released.
1-6. Refueling
1
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