Hiya guys new here so be gentle please

Ive got a 2.0 TDi 140 A6 which doesn't feel right.
If started from cold when being stood overnight it coughs into life, with a misfire for the first 3-5 seconds.
Then when you set off, under load if you plant the accelerator the car picks up slowly like its being deprived of fuel, very flat but it doesnt kangaroo, its just like your barely touching the accelerator. After a minute or so this clears up and its fine.
When warm it runs better but it seems a bit flat in the higher gears under load, the fuel economy doesnt seem the best (about 40mpg) and seems flat when pulling away in 1st unless you press the pedal further down.
I was thinking injectors after having a mondeo tdci but don't know what these are like for injectors. I was going to check the injection loom by measuring the pin resistances on the connector but have no idea of the pinout.
When i first got it, it had a misfire when warm on idle - the torsion was at -3.7 so i cracked both centre bolts of the cam pulleys round a bit clockwise and its now at 0 and runs smoother on idle.
Is there anything I could check? I tried doing basic setting in VCDS for EGR and the engine speeds up to about 1500rpm when you turn EGR off, but I didnt really understand what I was doing.
Im competent in electronics but never owned an VAG before so its all new to me.
Cheers
Andy