Hello there everyone, I'm a new member to this site.I have a 2001 Audi A4 TDI 130 which is beginning to give me some problems. While im driving at normal speeds the car drives fine but as soon as I come off the gas (i.e to slow down) and re-apply the gas pedal lightly, the car jerks as if its missing a beat. This happens in all gears and vag-com shows no codes. also noticed when taking off quickly a little more black smoke than usual appears in my rear view

I've recently had the maf and mapp sensor changed by the dealer so that would eliminate them (hopefully!)
I've also cleaned all the turbo intake pipes down to the intercooler and replaced as neccessary, so no leaks there.
I would appreciate any help.

Thank you in advance.........