I have a CEL telling me I have a misfire in cylinder #8 on my 98 cobra. I pulled the wire off of the coil pack and no change in engine rpm or sound. I swapped the coil packs and the misfire stayed on the same cylinder, I also changed the spark plug. The wire resistance is about 130 ohms. The problem was noticed after a tune up and and computer flash with a xcal3. Not sure if the problem existed before since the CEL didnt' work before the flash. I'm not sure what to check next. Any suggestions? thanks