See also:

Kia Soul owners manual
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Fuel requirements
Your new vehicle is designed to use only unleaded fuel having a pump octane number ((R+M)/2) of 87 (Research Octane Number 91) or higher. Your new vehicle is designed to obtain maximum performanc ...

Efficient, Powerful Engine
Available in two powerplants - a 2.4-liter four-cylinder or a 2.7-liter V6 engine - and two five-speed transmissions (manual with LX four-cylinder model only), the 2009 Kia Optima introduces a new ...