My '95 E300d has this curious characteristic---the many 0-rings in the fuel supply system fail one at a time in no particular order. The result is that wonderful diesel smell
in the engine compartment, with occasional odors in the cabin. I'm now about to replace them for the third time, It seems to me that these o-rings should last longer than two years. Should these rings be coated with lube or installed dry? Anyone have a similar situation? Thanks to all who reply.