Hi All, Any help here would be greatly appreciated! I have the above problems with my A4 170TDI SE S Line Avant,& im totally at my wits end!!!! Basically the car is lumpy on tick over & is fairly smoky too,its been in to a local garage (Lexus) who said they changed the MAF sensor & please see below what Teesside Audi have done,but i went to pick up the car from the Lexus garage & its still the same!! I now have the paperwork from Independent garage,who sent the car to Teesside Audi....basically they have changed the EGR valve & put in a new intake manifold vacuum unit....they then ran up the engine road tested & checked it & stated it was ok. I went to pick up the car from the garage who sent it to Audi & basically it is just the same!!...very rich smell & quite smoky like the first video thats in this thread.....surely you would think Audi technicians would have noticed this on tick over!.....very lumpy at just under 1000rpm & smoking like it is!!!...like i said im totally at my wits end now,Independent garage have dropped car back off with Teesside Audi & im going in first thing in the morning to basically start it up in front of Audi technicians & see what they say about it & basically ask ''can they rectify it or not'' & hopefully get it sorted!....i will be mentioning re coding the injectors & checking the cam belt alignment like it suggests in this thread,but if anyone has any more suggestions i can ask them to check,then please help. Cheers & Regards Paul W.