E 320 4MATIC Wagon (210.282) V6-3.2L (112.941) (1998)
Under car, after catalytic converter
O2S 1 (Before TWC) - G3/2
Under car, above and in front of catalytic converter
O2S 1 (Before TWC), Left - G3/3
Under car, on exhaust pipe at left of engine
O2S 1 (Before TWC), Right - G3/4