Audi 2.0 coupe juddering and choking

[vag2109]

Hi,
my 2 litre ABK coupe is a pain in the arse at the moment. It starts ok ,drives ok for a few mins, but then it starts cutting out, juddering, choking. When I step on the gas the revs don`t increase but rather it chokes and back fires. I have to pull over at this point, not able to drive it. The coil was changed made no difference. Recently it`s has new rotor arm, dizzy cap, fuel pump relay and ecu relay. Anyone have any ideas?

Thanks.