S4 B7 typ 8ED - misfire

[MarcDuffy]

Please Help!

I bought an S4 B7 typ 8ED a few months ago, love it!
I'm not great with cars, but always wanted a RS or S4 Avant.
2 months in it started to misfire.
I took it to a Volkswagen Audi Specialist who...

"check for misfire. Activate self diagnosis (seven faults stored).
Erase fault codes and live data.
Showing misfire on cylinders 1 and 2.
Removed plugs and check compressions, cyl 1 135 psi, 2 140 psi, 3 125 psi, 4 140 psi.
Swap coils 1 to 3 and plugs 2 to 4.
Still showing misfire on cylinder 1 & 2.
Supply and fit cylinders 1 and 2 injector.
Replace other 6 injector 'O' rings.
Still showing misfire on 1 & 2"

They did say they it was on a hunch changing the injectors and may not fix, but £828 later, no change.

They said try an Audi forum as they don't know what the issue is.

So here i am.

Any advice or preferred dealers would be massively appreciated. I'm near Tonbridge...

Many thanks in advance.