Kia Optima: Inflation PressuresAll tire pressures (including the spare) should be checked monthly when the tires are cold. “Cold Tires” means the vehicle has not been driven for at least three hours or driven less than one mile (1.2 km). Recommended pressures must be maintained for optimum vehicle handling, and minimum tire wear.

All specifications (sizes and pressures) can be found on a label attached to the front driver side door.
The correct tire pressure is 30 psi (210 kPa). The compact spare should be maintained at 60 psi (420 kPa).
WARNING - Tire Inflation
Over inflation or under inflation can reduce tire life, adversely affect vehicle handling, and lead to sudden tire failure. You could lose control and have a serious accident. Follow all the guidelines about proper tire maintenance.
Tire Care
Tire RotationComponents (2)
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Inside rearview mirror
Adjust the rearview mirror so that the center view through the rear window is
seen. Make this adjustment before you start driving.
WARNING - Rear visibility
Do not place objects in the rear seat ...
Central door locks
The central door locking switch is located on the driver’s arm rest. It is operated
by depressing the door lock switch. If any door is open when the switch is depressed,
the door will remain l ...