Hi, new to forum, have a 99 996 C4 that i picked up as a bit of a basket case. Finally have it about together and want to insure i am installing the o2 sensors correctly. I have 4 new bosch sensors, 2 pre and 2 post cat (13564 and 13753). Exhaust is stock. I understand bank 1 and bank 2, and grey and black connectors for pre and post cat. My question: are the connectors on the drivers side both for bank 1, or are the bank one pre cat and bank 2 post cat ( since those 2 sensors are located on the drivers side and closest to the connectors) what goes in drivers side connector?. Same logic for the pass side: bank 2 pre cat and bank 1 post cat? Otherwise the post cat leads would have to cross sides and the lead on the bank 2 post cat sensor is not long enough to route back to the pass side connector holder. make sense? Missing something obvious? If i had access to another 996 would be easy to get the answer, unfortunately none close by, so any insight appreciated.
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YOUR RESEARCHO2 sensor wiring question
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On the drivers side you have a black Bank 1 pre-cat sensor, and grey Bank 2 post-cat sensor. Passenger side is a black Bank 2 pre-cat and grey Bank 1 post-cat. Its because the exhaust crosses from one side to the other for packaging.
Welcome Cory, its one per side - i.e. left pre and post then right pre and post - they don't cross over. The factory manual has where each goes: Black connector - oxygen sensor in front of the catalytic converter Grey connector - oxygen sensor behind the catalytic converter Unless you're asking which goes into which plug - then im not too sure
And makes sense.. Appreciate the quick response
The connectors are different between the pre and post cat. You can't plug them in wrong.
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I can on my 02.
My RoW only has pre-cat so only one sensor per side... winning
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