#5 is the last plug back on the right bank
does it run well?
or,,,can you feel the miss
are you there?
i think you may need to also replace the spark plug boots
the boots are are what goes to the plugs from the coils
these will jump spark sometimes,,causing a miss-fire
on some models
i have an auto zone part#
for the boots
it would be best to chang all 6
but..if you must..you could do the one..to get you by till you replace them all
the boots may cost around $12+/-
i will give you directions on removing the coil