[V8] A8 misfire

[Bill Mahoney]

Hello,
Being an A8 owner and V8 list occasional lurker, I thought I'd try
posting here about another pals 97, A8, 3.7 ltr. Woes.
Trouble code is misfire cylinder #2
We have
Changed the plug
Swapped POS's
Swapped coils

Does this point in some general problem direction?  We will test wiring
from ecu to pos and pos to coil.  Then swap injectors and test injector
wires too.
Main fear of course is a bad ECU.
Any and all thoughts or comments would be much appreciated, especially
something like "Oh yeah, well of course it's the XXXXX."  
Thanks very much! (in advance;)
Bill m
95 1/2 S6 Avant
00 A8
75 Carrera