jroczniak

Mine was like yours, its been getting dramatically worse as the temp outside has fallen...anything below 55 or so and it stalls out a couple times like in the video.

yes the check engine light is on continuously.

spoon2000

I would get your friend with the VCDS connector to pull all your codes for you so you can post them to the thread -- I mean not only the VAG-COM codes, but also the OBDII codes.

jroczniak

Codes I was throwing Monday...:

The knock sensor and oxygen one were from before the issues started for sure...


5 Faults Found:
16711 - Knock Sensor 1 (G61): Signal too Low
P0327 - 35-00 - -
16825 - EVAP Emission Control Sys: Incorrect Flow
P0441 - 35-00 - -
16839 - EVAP System: Large Leak Detected
P0455 - 35-00 - -
17521 - Oxygen (Lambda) Sensor; B1 S1: Internal Resistance too High
P1113 - 35-10 - - - Intermittent
16486 - Mass Air Flow Sensor (G70): Signal too Low
P0102 - 35-10 - - - Intermittent
Readiness: 0010 1101

spoon2000

I would still tackle that O2 sensor sooner rather than later; I had one of those going bad on mine (although a different one that you have throwing a code) and fixing it seemed to help things. And if you have emissions inspection, you'll never get through with an O2 sensor going haywire. The repair shouldn't be hard to do -- I used the Bosch universal sensor (the kind where you have to re-use the original wiring harness plug and splice the wires to the new sensor) and it works fine. Some auto parts stores (I used Advance Auto Parts) will loan you the special O2 sensor socket kit -- it's must have to cut down on what would inevitably be a lot of swearing.

Perhaps someone else can chime in on which sensor the B1S1 one is.

After you get the O2 sensor done and get the changeover valve working, I'd erase all the codes, drive the car a couple hundred miles, then pull codes again to see what comes up.

And do give Audi a call at 1-800-FOR-AUDI to find out if your car had the MAF sensor recall work done.

Peter Badore

I would replace the mass airflow sensor or at disconnect it for testing. I have had very hard starting A6Qs with bad mass air flow sensors and also bad coolant temperature sensors that did not produce DTCs but still gave the ECU incorrect temperature values.
readings.

spoon2000

Just out of curiosity, what does disconnecting the MAF sensor do in terms of diagnosis?

Peter Badore

Disconnecting the mass airflow sensor takes that sensor out of the ecu inputs and uses a a default mode that will allow the engine to run satisfactorily but
not as designed (other inputs or fixed parameters are substituted). This procedure has surprisingly worked for me a number of times. Try it and see what I mean.

Peter Badore

B1S1= B1 is the right cylinder bank when sitting in the car, S1 is the O2 sensor in front of the catalytic converter on the right side.

SloopJohnB@mac.com

sounds like not getting fuel...how about monitoring fuel rail pressure while this is going on?
Could be a clogged fuel filter or dying fuel pump.

SloopJohnB@mac.com

2nd. Good kluge...if it works fuel pressure is ok. If not, chances are it's clogged fuel filter or fuel pump.