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.

InstallationDon't let your parking brake
freeze
Under some conditions your parking
brake can freeze in the engaged position.
This is most likely to happen when there
is an accumulation of snow or ice around
or near the rear brakes or if the ...
Inspection
1.
Measure the pressure of high
pressure line by measuring voltage output between NO.1 and NO.2 terminals.
2.
Inspect the voltage value whether
it is sufficie ...
Tire rotation
To equalize tread wear, it is recommended
that the tires be rotated
every 12,000 km (7,500 miles) or
sooner if irregular wear develops.
During rotation, check the tires for
correct balance.
...