01 S80 2.9 N/t Running on 3 cyclinder?

So we checked out the car and took out the plugs and notice #1,2,3 cylinder have burnt spark plugs. So we check the compression to the engine and it is good.. fuel good... spark good. So we put in 6 new spark plugs and swapped out the coils from 4,5,6 and the car is still running on 3 cylinders. So i was wondering anyone ahve any idea why it is doing this? The compression is goos and it have spark and fuel. Also you can smell a nasty exhause smell from it.

i took my rough idle volvo in for service and found out the same 123 had not been firing..swaped coils and it worked same then he went to check wire looms out and found nothing strange,taped up all the wiring again cleared the codes and it started fine,needed no parts just 1.4 hrs labor...we we both baffaled