I have an 04 S60R where cylinder 1 is not firing. I talked to my neighbor who is a mechanic and it still isn't firing. i switched the spark plugs from cylinder 1 and 2 and the spark plugs are fine and i did the same to the coil pack and they both work in 2 but not 1.

 

So the next thing is to check the wire harness coming to #1.