First let me start by saying hi to everyone and base on the psting on the forums you guys are very helpful. First Audi first post.

Bought a 2000 A6 2.7T about two weeks ago with 110,000 miles. At the time I bought the car the chech engine light was one. The guy I bought it from said the O2 need replacing. He had a new one he gave me. Cleared the code and the light went out, which it should so I drove the car for about 50 mile when the light came back on. I then ran a scan on got the following.

VAG-COM Version: Release 311.2-N


Chassis Type: 4B - Audi A6 C5
Scan: 01,02,03,08,15,16,17,35,36,37,45,55,56

Address 01 -------------------------------------------------------
Controller: 4B0 907 551 L
Component: 2.7l V6/5VT G 0003
Coding: 06652
Shop #: WSC 02325
4 Faults Found:
17521 - Oxygen (Lambda) Sensor: B1 S1: Internal Resistance too High
P1113 - 35-10 - - - Intermittent
16805 - Warm Up Catalyst: Bank 1: Efficiency Below Threshold
P0421 - 35-00 - -
17538 - Fuel Trim: Bank 2 (Mult): System too Lean
P1130 - 35-10 - - - Intermittent
17536 - Fuel Trim: Bank 1 (Mult): System too Lean
P1128 - 35-10 - - - Intermittent
Readiness: 0000 0000

Address 02 -------------------------------------------------------
Controller: 4B0 927 156 BD
Component: AG5 01V 2.7l5VT USA 3131
Coding: 00002
Shop #: WSC 00000
1 Fault Found:
17125 - Torque Converter Clutch Circuit Performance or Stuck Off.
P0741 - 35-00 - -

Does this sound like the O2 and if so there are 4 of them a it appear that it is Sensor 1 bank 1, not sure where that one is? Also what will cause the 17125 -Torque Converter Clutch Circuit Performance or Stuck Off.

Thanks

 

Bank 1 Sensor 1 is passenger side in front of the cat. That code usually means you need a new o2. The torque converter code usually means you need a new torque converter.

 

So the Torque Converter Clutch Circuit Performance or Stuck Off is the coverter going out and not something like a trans fuild and filter change fix. I have noticed that is the cold mornings the gear changes slip pretty bad. Once it warms up not as bad, so does everyone feel that the converter is shot?

 

nop fluid and filter change first

 

I agree, fluid change relieved my trans problems and improved drivability.

 

Thanks guys I will try that first. Now if I can just back the darn bank 1 sensor 1 O2 sensor a loose.

 

you also have lean codes that i doubt the o2 sensor is causing b/c its both banks. the o2 being bad would cause the converter efficiency code. if you get the new o2 in and check engine light comes back more than likely you need a maf as well.

 

This will not make the converter code go away we have been over this before....right?

 

about the code in the tcm you need a new convertor,2,7 t has a problem with it.about the o2 go to addres word 01 basic setings 04 adres 107 and see the value they shoud be around 7% if difrent check maf or for air leaks.than go to 04 -047 and 046 to see if o2 is responding to the load

 

hello i have the check engine light with code 0741 on my 01 a6 2.7t and i when to the dealer to get the estimate for how much it would cost and the gave me estimate for 3200. But the mechanic said that their is no noticable difference with that problem. He also said that most of their a6 2.7t loaner car have the same problem and that that is a common problem with that this model. So all i do is whenever the check engine light comes on i jus erace the code it comes on like twice a week.