O2, Oxygen Sensor, Front or Primary (Bosch) for Mk I TT 1.8T, B6-A4 3.0L, C5-A6 3.0L, C5-allroad and B6-B7 S4 4.2L V8

These Front O2 sensors are OEM Bosch replacements for the 04 to 08 B6/B7 S4 w 4.2L 40v V8. They retain 100% OEM fitment and include the connector. We highly recommend replacing both as a pair.

Please Note, when diagnosing your vehicles: Bank 1 = passenger’s side/right, and Bank 2 = driver’s side/left.

2 per vehicle, adjust the quantity to 2 at checkout if you want both.

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