Has anyone ever fixed this problem when it wasn't the coils or spark plugs?

 

Because there are several possible reasons for a misfire to take place, it will require each possibility to be eliminated one by one.

Keep in mind it could be electrical or fuel related, which now could include vacuum leaks. So you see there is no simple fix unless one stumbles upon the cause .

What is important to know is , does the misfire take place at certain times ,under certain operating conditions like at idle or certain speeds , loads or maybe certain temp conditions.