Hi everyone,

I hope I'm not going to create a double post (couldn't find anything similar). I have a A6 2.0L UltraTDI 2015. My issues started last year in April when the DPF light came up on my dash. I had an error for the O2 sensor which I replaced. Since then it keeps coming and going all the time. After it comes up, if will not take it on the motorway to do a regen, eventually it will go into limp mode with error DPF regeneration duration. In the last year I've replaced the O2 sensor, EGT2 sensor, turbo, EGR. Nothing changed. I took my car to 7 different garages including Audi garage and Audi specialists garages. No one can find the reason. I've cleaned the DPF with one of those company that comes to your house and does it but nothing changed. When I have the DPF error on my dash it's not showing anything on VCSD. Any ideas of what might be? Thank you

10 minutes ago, DanDum said:

Hi everyone,

I hope I'm not going to create a double post (couldn't find anything similar). I have a A6 2.0L UltraTDI 2015. My issues started last year in April when the DPF light came up on my dash. I had an error for the O2 sensor which I replaced. Since then it keeps coming and going all the time. After it comes up, if will not take it on the motorway to do a regen, eventually it will go into limp mode with error DPF regeneration duration. In the last year I've replaced the O2 sensor, EGT2 sensor, turbo, EGR. Nothing changed. I took my car to 7 different garages including Audi garage and Audi specialists garages. No one can find the reason. I've cleaned the DPF with one of those company that comes to your house and does it but nothing changed. When I have the DPF error on my dash it's not showing anything on VCSD. Any ideas of what might be? Thank you

Hi did you readapt the O2 sensor and the DPF after it was cleaned as it has to learn its new soot/ash levels from empty, if so and it still keeps doing it it may well be the DPF pressure sensor, thats the one with two pipes that measures the gas flow pressure before and after the DPF  if its not performing as it should it allows the DPF to fill up to far before trying to initiate a regen, check your soot levels as they should not exceed 30 grams.

Steve.

The O2 sensor was replaced by a garage, I hope they readapted. I noticed I have 2 pressure sensors (one has both ends connected and the second only one) and they are next to eachother. Should I replace them both?

21 hours ago, DanDum said:

The O2 sensor was replaced by a garage, I hope they readapted. I noticed I have 2 pressure sensors (one has both ends connected and the second only one) and they are next to eachother. Should I replace them both?

Hi the one with only one connection is for the low pressure EGR, the sensor with two pipes is the DPF sensor they are both the same part number but the EGR sensor on the low pressure side uses barometric  pressure from the open side to make its calculations, replacing both is not a bad shout but they will both need adapting, I would still be interested in your soot/ash loadings.

Steve.