Kia Optima: Fuel Filler Cap. Description and OperationDescription
A ratchet tightening device on the threaded fuel filler cap reduces the chances of incorrect installation, which seals the fuel filler. After the gasket on the fuel filler cap and the filler neck flange contact each other, the ratchet produces a loud clicking noise indicating the seal has been set.

InstallationSeat height
To change the height of the seat, move the lever upwards or downwards.
To lower the seat cushion, push down the lever several times.
To raise the seat cushion, pull up the lever several times. ...
Underdrive Brake Control Solenoid Valve(UD/B_VFS). Schematic Diagrams
Circuit Diagram
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