Impala V6-3.9L (2007)
6. Remove the exhaust manifold heat shield.
7. Remove the upper catalytic converter to exhaust manifold nut (1).
8. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
9. Remove the CPA retainer (1).
10. Disconnect the HO2S electrical connector (3).
11. Remove the HO2S.
or
Heated Oxygen Sensor 2 Replacement for the 3.9L engine.
12. Support the exhaust system.