BMW Repair Questions? Ask a Mechanic for Answers ASAP
The problem is your Crankcase Vent Valve has gone bad and will need replacement. It is allowing major buildup of pressure inside your engine which will do major damage internally quick. So do not run it unless the dipstick is pulled out so the pressure has somewhere to escape. The noise you are hearing is the pressure inside the engine escaping past the rear main crankshaft seal thats why you have the high pitch noise.
If you give me the last 7 digits of your VIN # XXXXX will look up the part for you.
Liz these should be the correct parts that you need to change, # XXXXX is the Crankcase Vent Valve. You will also need # XXXXX
Thank you very much for the Bonus,
Thank you very much again I closed the other question for you so you will not have to worry about it.