Rear Heated Oxygen Sensor

Disconnect the negative (-) battery terminal.
Disconnect the heated oxygen sensor connector (A).

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Remove the connector (A) from the bracket by pulling it in the direction of arrow.

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Separate the rear heated oxygen sensor wiring from the fixing clip (A).

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Remove the rear heated oxygen sensor by using the SST (09392 - 1Y100 or 09392-2H100).
Tightening torque:

39.2 - 49.1 N.m (4.0 - 5.0 kgf.m, 28.9 - 36.2 lb.ft)

Courtesy of KIA MOTORS AMERICA, INC.