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Oxygen Sensor: Service and Repair

Primary HO(2)S and
A/F Sensor (F23A4 engine) Replacement


Special Tools Required
O2 sensor wrench SNAP-ON YA8875 or SP Tools 93750 or equivalent, commercially available

Primary HO(2)S and A/F Sensor:




1. Disconnect the primary HO(2)S or A/F Sensor 4P connector, then remove the primary HO(2)S or A/F Sensor (A).
2. Install the primary HO(2)S or A/F Sensor in the reverse order of removal.


Secondary HO(2)S Replacement

Special Tools Required
O2 sensor wrench SNAP-ON YA8875 or SP Tools 93750 or equivalent, commercially available

Secondary HO(2)S:




1. Disconnect the secondary HO(2)S 4P connector, then remove the secondary HO(2)S (A).
2. Install the secondary HO(2)S in the reverse order of removal.