Ok, I've got a 99.5 A4 Quattro w/ an AEB engine.

Over the last few days I've been working on taking care of a number of technical issues with my car. Namely, I've corrected a misfire issue because of a bad ground, installed new plugs, installed a new MAF, and installed a new universal O2 sensor (post cat). I still have a couple of more issues to take care of (ABS light, new front axles).

Prior to replacing these sensors, plugs, and tightening ground, when I ran VAG-COM I got:

Control Module Part Number: 8D0 907 557 P
Component and/or Version: 1.8L R4/5VT MOTR HS D07
Software Coding: 06201
Work Shop Code: WSC 06335
5 Faults Found:
16806 - Main Catalyst; Bank 1: Efficiency Below Threshold
P0422 - 35-10 - - - Intermittent
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-10 - - - Intermittent
16687 - Cylinder 3: Misfire Detected
P0303 - 35-10 - - - Intermittent
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-00 - -
16687 - Cylinder 3: Misfire Detected
P0303 - 35-00 - -
Readiness: 0000 0000

After replacing everything, the car has been running a lot better, but now I've got a new CEL

17606 P1198 O2 Sensor Heater Circuit, B1 S2 Electrical Malfunction

Also, when I run the O2 sensor check, i get the following

Sunday,03,May,2009,18:27:30:03151
VCDS Release 805.3: Generic OBD2

TID 01 - Rich to lean sensor threshold voltage Test:0.445 V
TID 02 - Lean to rich sensor threshold voltage Test:0.445 V
TID 03 - Low sensor voltage for switch time calculation N/A
TID 04 - High sensor voltage for switch time calculation N/A
TID 05 - Rich to lean sensor switch time N/A
TID 06 - Lean to rich sensor switch time N/A
TID 07 - Minimum sensor voltage for test cycle Test:0.000 V - Min:0.000 V - Max:0.400 V
TID 08 - Maximum sensor voltage for test cycle Test:0.000 V - Min:0.500 V - Max:0.945 V
TID 09 - Time between sensor transitions Test:0.000 s - Min:0.120 s - Max:1.520 s
TID 10 - Sensor period N/A

Before I send this O2 sensor back for replacement, any ideas as to something else I can check?

 

a universal o2 as in it didnt have the harness on it already? if thats the case, i would recheck your wire splice/solder work to make sure that all 4 wires are connected to the right places and are soldered well. if you find that you swapped any of the wires by mistake, also check the fuse that the rear o2 sits behind (should probably check it anyway to be sure)