2015 Audi 2.0 TDI CNHA - Black smoke

[DoctorTox]

Good evening esteemed forum members

I recently acquired a bit of a problem child of a car for a proper (hopefully) steal.

It had been stage 1 tuned, DPF off and Adblue off.

When i bought it, it ran rough and low power across the whole band, with thick white smoke intermittently, and heavy black smoke on full pedal.

I was hoping it was something as simple as a bad tune, so i called in a favor and had the ECU flashed to an original file.

It runs significantly better, and the intermittent smoke is reduced, so is the black smoke, but it’s still there.

I have had it logged, and on full pedal the lambda reads a steady 0.85, which seems very low.

So heres what i know so far:

DPF is emptied out, but still in position with all the original sensors etc.
EGR is still there
Turbo was replaced by previous owner, aswell as some other things, i’m getting a list by the shop who did it.

On DTC scan i get this:

P0405 EGR valve position low input
P0403 EGR circuit malfunction
P0420 Cat converter bank 1 low efficiency
P204B Reductant pressure sensor

I have CEL and the Adblue no start in 1000km warning.

Since the DPF has been emptied i know i will need a custom map, and i fully plan on blanking the EGR and turn off Adblue aswell. But i would like to rule out any other problems before doing this to avoid issues down the line.

Any ideas?

[Crasher]

DPF off and Adblue off.

I won't help with cars where this has been done.

[DoctorTox]

Well, right now it’s bonestock, except for the cleared out DPF. If i could find a new DPF for a reasonable price i would have it fitted, removes any headaches about not passing MOT.

As i stated in the post, i want to fix any issues with it, and if i can have it running good without any modifications i’d be happy to.