Hi I've got a 1996 A4 1.9Tdi and its giving me problems starting,
Called out the AA today and he said it was the non return valve (??) that was letting in air to the fuel system. He pointed to a small white box with a fuel line going to it and one coming out of it on the top right of the engine.
The problem is... what is it called so i can order a new one from Audi
Apart from that this is my first Audi and my first diesel and i am well impressed with the fuel consumption i am getting