I just bought a 2002 E320 wagon via Ebay- 1600mi. drive home, and it seems perfect, except for a slightly rough idle. The shop I had check it out prior to paying for the auction recommended replacing the plugs, and quoted me $320 to do it!!???
Is there some trick to this, or do I need to remove part of the intake to get at the plugs? I know there are 2 per cylinder, but I just can't comprehend 3 1/2 hours of labor and $8 per plug to do it.
Any advice?? If it's just time consuming I'll do it myself, but if there's some component removal involved, I'll get it done at a local shop.

 

Fiddly job but straight forward. No special MB tools. Just a 3/8 drive socket set with plug socket. Just poor access.
OE plugs (Beru) are expensive but I recommend them (Platinum)
Change point seems to differ country to country but are good for a minimum of 50k.
DO NOT overtigten plugs. Use copperslip or similar release agent...otherwise you wont get the plugs out next time around,
Stuart.