BMW 320d DIESEL - black smoke + poor acceleration

Hi all,

Hope you can help!

I have a 320d. Getting lots of black smoke coming out of the exhaust when going up and hill or under heavy acceleration. Acceleration is also flat.

I've clean the EGR valve and PVC. Done an oil change and changed the air, fuel and oil filters.

Any idea what I can check guys?

Thanks

Shaun