2008 Audi A3 1.9tdi BXE Misfire

[Cozen]

Have a 2008 Audi A3 that has a rough misfire at idle shakes violently, when you bring rpm up it smooths out a bit but you can still feel the misfire. There is 4 fault for all the glow plugs but I don't think it will cause the misfire, but has a P0304 cylinder 4 Misfire. I checked the connections for cylinder 4 injector and the cam lobes and it looked all ok. I'm leaning towards the injector. Smooth idle running stabilization quantity are :
Cyl 1 : 2.21
Cyl 2 : -2.01
Cyl 3 : -3.00
Cyl 4 : 2.58
I'm leaning towards the injector on 4 cylinder or are they all kaput. Any help appreciated..

[Gazwould]

You've got some big end bearing shells to do too !

[Crasher]

I haven’t seen that for a while, what looks like all four injectors in trouble, if anything number 3 is the worst but in my experience ANY value over +/-1 mg is cause for concern.

[Cozen]

Why do I get only cyl 4 Misfire code and not cyl 3 or any other?!

[Crasher]

Without being hands on I would suggest a new injector on number 4 first and then see what the values are. Fit a new head harness as a matter of course.