Hello all,

Check engine light came on about a month ago. I got the following error (see VCDS output below). Checked the forums and the suggestion was to replace the O2 sensor after the CAT. I replaced it and cleared the codes and it came back. Now I'm thoroughly stumped on what it could be besides having my CAT rebuilt. I don't know if it's a coincidence, but I had just ran the first tank of fuel with Liqui Moly Jectron Fuel Injection Cleaner and was starting on the second tank when all this happened. I read somewhere on here that they fixed it by running low quality fuel through it. I still have about 1/2 a tank of premium with Jectron to get through before I can test out that theory.
(FYI - I always seem to have the DTC Memory Error, it never goes away)

Any other ideas on what to try?

Here is the VCDS from Engine I and II:

Address 01: Engine Labels: 07L-910-552-BSM1.clb
Control Module Part Number: 4E0 910 552 K HW: 4E0 907 552 A
Component and/or Version: 5.2L V10/4V FSI ª0040
Software Coding: 01060009190F0260
Work Shop Code: WSC 26153 444 103839
VCID: 2A0D108530FA95FA217-807E
1 Fault Found:

006435 - Please Check DTC Memory of ECU Number 2
P1923 - 008 -
Freeze Frame:
Fault Status: 01101000
Fault Priority: 2
Fault Frequency: 1
Reset counter: 255
Mileage: 257789 km
Time Indication: 0
Date: 2024.09.07
Time: 16:07:30

Freeze Frame:
RPM: 0 /min
Load: 0.0 %
Speed: 0.0 km/h
Temperature: 87.0°C
Temperature: 67.0°C
Absolute Pres.: 990.0 mbar
Voltage: 11.303 V


Readiness: 0000 0000


Engine 2:
Address 11: Engine II Labels: 07L-910-552-BSM2.clb
Control Module Part Number: 4E0 910 552 K HW: 4E0 907 552 A
Component and/or Version: 5.2L V10/4V FSI ª0040
Software Coding: 01060009190F0260
Work Shop Code: WSC 26153 444 04929
VCID: 2A0D108530FA95FA217-807E
1 Fault Found:

004476 - Bank3; Oxygen Sensor Correction; Behind Cat
P117C - 002 - Lean Control Limit Exceeded - MIL ON
Freeze Frame:
Fault Status: 11100010
Fault Priority: 2
Fault Frequency: 4
Reset counter: 255
Mileage: 257590 km
Time Indication: 0
Date: 2024.09.07
Time: 09:02:35

Freeze Frame:
RPM: 2926 /min
Load: 47.4 %
Speed: 133.0 km/h
Temperature: 95.0°C
Temperature: 28.0°C
Absolute Pres.: 1000.0 mbar
Voltage: 13.335 V