BobGA8

Hello All,
I am in the process of changing my up-stream, bank 2 oxygen sensor on my 2012 A8. Getting the sensor out of the cat was the easy part; however, removing the electrical connector from the metal clip is a major pain. I have tried pulling it out numerous times with all the strength I can muster to no avail. Is there's some trick to this? Any tips?

Thanks,
Bob
2012 A8L

BobGA8

Crickets. . .

BobGA8

OK, apparently no one has changed a pre-cat, driver's side O2 sensor. Finally got it done. Here are the steps:
1) remove breather tube (2 clamps on either end) and engine beauty cover
2) disconnect electrical connection (tight squeeze in front of firewall) and cut zip tie that holds it to the other O2 sensor wire
3) remove O2 sensor (7/8" crow's foot or O2 sensor socket). Comes out easy.
4) The hard part - if you try to do this with your hand - is getting the electrical connector (attached to sensor) out of the metal prongs that hold it in place. I struggled to pull it out by hand but could not. I didn't want to break anything but finally resorted to prying up (with socket extension) on bottom of connector. Managed to get it out w/o breaking it.
5) tread new sensor (torque: 40 ft/lb) in and connect electrical connector (new sensor comes with anti-seize on threads)
6) new zip tie on wires
7) push electrical connector back into metal prongs
8) reconnect breather tube and beauty cover.
9) reset CEL with Autel Maxidas (or equivalent)

This will probably take less than 45 minutes next time it needs to be done. The post cat sensor on this side is slightly more accessible and should take a little less time. The other side (passenger) looks a little more fiddly as a few more things need to be removed. Dealer price on sensor ranged from $210 - $300. Got mine at AudiUSAParts for $200. Hope this helps.

Best,
Bob

rally

Thank you for the write up! It’s not fun to be the guinea pig but it really helps everyone else.

Sebastian Carlos

what symptoms were you getting that made you want to change that o2 sensor?

BobGA8

Hi, the engine threw a code indicating a failing O2 sensor.

Sebastian Carlos

was it the post catalyst too lean code? p2096?

did you experience any symptoms or just the code


thanks

BobGA8

I don't remember the code number but is was the bank 2, sensor 1 (up stream) one. No obvious symptoms, just the check engine light.