Does it make sense to change just the 1 coil gone bad or should I change all 6 on my '04 A4 3.0Q?

 

i have the same question, too.

now my cylinder 5 misfires sometimes. only cylinder 5.

read the DIY coil pack, seems pretty easy, just unplug the wire and pull coil out and back in again. thatz it.


i've replaced all spark plugs to NGK Platium 1 month ago.
didn't replace coil packs at that time though.

 

I dont think u actually need to unless you have some kind of a misfire. But if u thinking about going with Hitachi or R version and if you got some extra $$$, Go for it, but keep your stock ones in a trunk as a spare, just in case.

 

Personally I just keep an extra coil in my trunk. But unless you're made out of money... dont bother replacing them all. But like AUDIPROTEIN said, go for it if you plan on going with Hitachi or something similar since I heard nothing but good on those