What octane gas should I use in my 2006 Kia Sorento?

I just bought a 2006 Kia Sorento and there is no owners manual. I have been putting 85 octane gas in it(that is the lowest in my state) and was wondering if I should use 87 (which is the lowest in most states). If you have a 2006 Sorento, would you please tell me what the manual says to use. Thanks a bunch...|||ur fine on 85 car manufactures design cars to run on "pump" gas or "unleaded" gas which is all gas..unless the car is turbo charged or running hi compression which its not then ur all set..|||if you haven't been having any problems then I wouldn't worry about it. if you have been getting engine knock or your check engine light has came on then up the octane. your car isn't supercharged or turbocharged so there no need for higher octane to prevent spark knock.|||The Kia dealership can answer any question you may have about the vehicle, Most likely 87 is the octane it uses. I only know of luxury high end expensive vehicles that must use 91 octane or higher.|||A Kia? They will run fine on 85 octane. In Korea, where they are made, the best they can get is 80. Good luck.