Hi all, I have been getting a CEL and code 16690, cylinder #6 misfire, on my 96 A4 2.8 12v. I changed the plugs and wires because they were a little over due, but I was still getting the 16690 code, the engine will run fine and smooth then for a few seconds it will run rough then it goes back to running fine. Then I changed the coil packs, and it is still getting the same code. Does anyone have any ideas????

Thanks in advance