Just replaced a bad sensor on an X3 last week. In this case the sensor gets wet with oil, how it could run down the wiring and fry your ecu is beyond me, I mean HS that is a lot of oil and perfect travel.
Any ways, replace the sensor, blow away the oil best you can and try, it really is a simple job (can you remove the VC on your own) and inexpensive part $XXX. I know the dealer has the ability to scan the ecu and see what component shows improper communication, like with your shaft sensor for example or valvetronic motor. Sooooo if after replacing the sensor if the issue continues I would consider the specific wiring/harness ONLY if a dealer scan shows direct relation between bad info to it from the ecu. If you truly damaged the ecu you shouldn't have just an issue with the shaft sensor, many more issues should be present. Take it one step at a time, bad ecu's are not unheard of but because of a bad shaft sensor leaking oil, very weird but you say it was there so...
It is quite possible you have a bad ecu period and the other issue(s) are symptoms of that or other issues. There is no reason why a bmw dealer cannot scan and tell you what the real issue is, the ecu itself or the shaft sensor.
Last edited by Blackedout95; 05-21-2013 at 12:35 AM.