While I generally agree with Kestas' comment, I will say that our E320 has had the head gasket replaced twice now for oil leakage issues...once at around 80k and once at 120k. The harness did survive.

__________________
________________________
2002 Mercedes-Benz E320 4Matic
1995 Mercedes-Benz E320 Wagon
2005 Land Rover LR3 V8 SE
1999 Audi A8 4.2L quattro