After replacing 2 ignition coils, one of the cylinders still gave a misfire upon redlining the car. The spark plugs are relatively new so I decided to refresh the still original ignition wires.
There are 16 of them with different lengths and part numbers. If you want to get the OEM set, that is Bosch 09850. I got the set for $175 which is much cheaper than buying the 16 wires individually between $15-$25 a piece. Below are the individual part numbers for Bosch and Mercedes for reference.
9x “G” – Bosch # 0356912948 (Mercedes OE # 112 150 01 18) 24.7 cm
4x “K” – Bosch # 0356912950 (Mercedes OE # 112 150 02 18) 26.7 cm
2x “H” – Bosch # 0356912952 (Mercedes OE # 112 150 03 18) 29 cm
1x “L” Bosch # 0356912954 (Mercedes OE # 112 150 04 18) 31.7 cm
And here you can see old and new comparison:
The engine banks have labels for which cable letter goes where and the coils do as well so it should be fairly straight forward to replace them. I found it easier to unplug everything old first, plug the new wires into the spark plugs only and then plug into the coils one by one.