2005 A8L 4.2L miss in #2 cyl ?????
 

Hello I have a 2005 A8L with 100k on it the engine light comes on and flashes then stays on had the code read and it said misfire in #2 i pulled the plug and checked it it is sparking ??? any ideas it has a ruff idle

It may not be sparking enough....need to switch that coil with another, to see if misfire moves there, then it is a bad coil.
If the misfire stays the same (#2), the fuel injector to that cylinder will also produce a misfire code or wires/plug are bad to that coil. Check wires to coil, to assure they are getting same signal as other working coils...if so, then check resistance reading on that injector compared to other known good ones. If the same, then check wires/plug to that injector.
MOST likely a bad coil...most common cause of a single cylinder misfire.