my v6 2004 touared has a misfire issue cylinder#1,2,3 are working but 4,5,6 are giving misfire error in other words they are not working what are the possible cause of that

I'd look at the system ground....the loop end of the 1/0 battery cable as it attaches to chassis ground...wirebrush this lug with a pliers in one hand and wirebrush the spot where the lug was bolted to.....for full and steady ground potential...at the same time resetting the computer~

i have done that but it's the same thing. i mean 3 cylinders are working while the other 3 are not working. i tested if current passes to the coils. i discover that there current in coil wire No 1,2 and 3 but there is no current in coil wire no.4,5and 6

I have a 04 vw touareg v6 i cahnge the spark plugs and coil pack and i keep getting random misfire what i have to look next tia