Yes I have a leak there!!! I cleaned a max with wd40 , but its still running bumpy...grrrrr.... Thanks for your reply and link
If you have an oil leak from the crankshaft sensor , you need to get the cables cleaned or replaced and the sensor changed , and a safety cable sold by Mercedes installed to prevent re-occurance , otherwise if the oil reaches it , you can ruin the ECU which is a very expensive repair in the thousands !!
The parts are relatively cheap and easy to replace , well worth it for peace of mind .
Check your engine type is M111 and if it is the references for the parts needed are as follws :
1 x 271 -150-27-33 Cable
1 x 111 -051-01-77 Sensor
1 x 111- 997-01-86 Sensor centre cover
It is also advisable for owners of the M271 engine to put two of the cables in place before the crankshaft sensor , as according to the forum MBFaq , where I got these references from , cases of the same problem have occured in this engine also , although the M111 engine is more prone to the fault !