S4 V8-4.2L (BHF) (2004)
1
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4-pin connector for Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2
(behind Three Way Catalytic Converter (TWC)) -Z30-, bank 2
4
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6-pin connector for Heated Oxygen Sensor (HO2S) 2 (-G108) and Oxygen Sensor (O2S) Heater 2 -Z28- before catalytic converter, bank 2