2002 lincoln ls 3.9 misfire cylinder #3

Hello fellows! I am new member of you car enthusiasts hope I could be help and be helped at the same time. hope I can make some new e-friends out there!
right now I I'm trying to help a friend with her carrito but this thing has turned into a nightmare everything checks ok so far that seems to me this is something unusual. I've been reading your posts and tried everything so far but no luck so far.
Fuel pressure is fine, compression ok, no problems with valve covers, coils and plugs ok, (I swapped them), no air leak,so far nothing has worked to fix it.
Does anybody out there has had this kind of problem? cause my gun is getting oiled but before I used I want to hear from you guys! Thanks.

You mention you've swapped coils and plugs. So even when doing that, the misfire always remains on cylinder #3? Did you reset the diagnostic codes each time you swapped plugs and/or coils around?

-Rod