HELP!! 02' C240, while i was driving the vehicle made a very slight "tink" noise then began to have a slight miss on acceleration, and check engine light came on. At cruising speed it is hardly noticable. I put a scan tool on and it came up "Miss Cyl 5". Replaced coil pack as it was firing off to the side. Replaced all 12 plugs, and all 12 plug wires. Still have same problem. Anyone's help would be much appreciated. ! Thanks, Wayne