Front Heated Oxygen Sensor

Disconnect the battery negative (-) terminal.
Disconnect the Heated Oxygen Sensor (HO2S) connector (A).

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Remove the connector (A) from the bracket in the arrow direction.

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Remove the front HO2S (A) 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.

Courtesy of KIA MOTORS AMERICA, INC.