Looking for some help with my A3 O2 sensor

[3G3T7I]

My A3 is indicating the following faults as reported by VAG COM:

008819 - Oxygen (Lambda) Sensor Signal B2 S2: too Rich
P2273 - 002 - Lower Limit Exceeded - Intermittent - MIL ON
Freeze Frame:
Fault Status: 10100010
Fault Priority: 0
Fault Frequency: 4
Mileage: 100232 km
Time Indication: 0

Freeze Frame:
RPM: 2126 /min
Load: 28.2 %
Speed: 82.0 km/h
Temperature: 81.0°C
Temperature: 12.0°C
Absolute Pres.: 1010.0 mbar
Voltage: 14.351 V

008345 - Post-Catalyst Oxygen (Lambda) Sensor Correction; Bank 2: Too Rich
P2099 - 001 - Upper Limit Exceeded
Freeze Frame:
Fault Status: 01100001
Fault Priority: 0
Fault Frequency: 2
Mileage: 100254 km
Time Indication: 0

Freeze Frame:
RPM: 2079 /min
Load: 30.2 %
Speed: 81.0 km/h
Temperature: 84.0°C
Temperature: 31.0°C
Absolute Pres.: 1010.0 mbar
Voltage: 13.843 V

So it would appear I need an O2 sensor. Looks like I'll be getting one from the dealer so I can get it done this weekend. Can anyone tell me which side is bank two? I have not been able to locate a diy and would appreciate any ideas or assistance. Thanks in advance.

[3G3T7I]

Got it, Bank 2 is driver side. Just waiting for a delivery from GAP.

[sTT eV6]

Depends which side the steering wheel is on..
Steve

[SilverSquirrel]

Got it, Bank 2 is driver side. Just waiting for a delivery from GAP.

did the o2 sensor do the trick? getting similar faults

[A4qguy]

did the o2 sensor do the trick? getting similar faults

I have these same fault codes.
Rough iidle, fuel consumption has gone up like 20%, lots of black smoke on acceleration.
What I want to know is if this code means:

1. The o2 sensor is the problem and is causing the over-rich mixture in bank 2
OR
2. The o2 sensor is just reporting an over-rich mixture in bank 2, but something else is actually causing it.

And yeah, would love to know if swapping the sensor solved it,

[SilverSquirrel]

new front sensor solved my issues. No codes since. mileage improved slightly, smoother idle.
im at 80k, so thinking about doing the other bank as well

[A4qguy]

new front sensor solved my issues. No codes since. mileage improved slightly, smoother idle.
im at 80k, so thinking about doing the other bank as well

Nice, thanks for the follow-up.
I was getting codes on Bank 2 for both Sensor 1 and Sensor 2, which I guess is normal because if Sensor 1 goes far enough out of whack and causes a bad mixture, then Sensor 2 will be reading the effects of that as well and throw a code, but it doesn't mean Sensor 2 has a problem.
To check this I idea, I changed only Sensor 1 on Bank 2 last night (a surprisingly easy job once you get the airbox out to reach it) and it now runs perfectly, mileage is back to normal, no more codes.

[SilverSquirrel]

.

[kgw]

Just to round out the knowledge on these issues; my engine idle went bad recently: sounded like a basket of parts rattling around! Exhaust was funky, with the sulfurous odor. Still had power when off idle. Hooked up VAD Mobile and found no DTC's, but the Bank 2 O2 sensor was pegged at a value of 25 whenever the engine was off idle, and the tailpipes were sooty. Strange. . .Next day, I hooked up VAD Mobile again and had DTC's: random misfire, misfire in 5 and 6. I had 2 new (old non-B revision) coils to swap in, and now things are back to normal. Or so it would seem. . .Unless it's something else, like the MAF is heading south.