DPF regeneration

[Leighspain1975]

Hi Guys

Little stumped on this one if anyone can help?.
I have an A7 3.0tdi 2012.
Really simple question. Before Dpf regeneration engine sounds like a bag of nails and runs rough. After Dpf regeneration engine is a bad of nails and runs rough. But during Dpf regeneration the car is silky smooth and responsive no clatter it basically runs perfectly.
I pretty sure it’s regenerating because with the engine off the fans keep going.

What’s going on here?.
What’s happening to make this run smoother?.
Is their a sensor bad somewhere?.

I have no idea please help.


Cheers

 

[ChetA6]

I’d like to echo the above comments too, my new c8 40tdi definitely feels smoother and more powerful when on a regen!, any thoughts?

 

[Leighspain1975]

Thanks for joining me on this one.
Thought I was going crazy.
Don’t know about yours but I notice the engine much quieter and seems more responsive and less snatchy in slow traffic too. The usual injector pinging noise goes away too.

My mechanic suggested it’s the EGT sensors at fault but I’m not convinced.
I think it’s something with the injector timing being slightly out of whack?.