I have a 1996 328I with 225000 miles on her. The problem is the "o" ring gasket (The Large 4'' one) for the screw cap to the oil filter housing bloats out and leaks when you run the car. The bloating is about 3/4 of an inch and is never in the same spot after re-adjusting.
This is the third "o" ring, the last one came from a BMW dealer. The housing isnt damaged and the "o" ring I even torqued down to the specified 25 nm (18ft,lbs) which it calls for.
The only other thing I have noticed is when I leave the car over night and pull the dipstick to check the oil the next morning you can actually hear the oil from inside the tube trickling back down in to the pan.
By the way the two small o rings that are on the oil filter cap assembly have never been replaced.
Could these o rings cause a possible pressure problem?
Any avenue I can pursue I would greatly appreciate, not to mention the faster I fix this the faster my wife drives the car again and stops complaining! Thank you in advance!