Had frequently many problems with car. I will start with the noise coming from the engine when it was cooled down(especially in the morning). Once it get warm the noise faded away. Few months ago it got really worse and I took to my garage. My mechanic suggested to change the timing chain and also found that camshaft was broken. I fixed it for nearly for 1700Euros.
After few weeks, again had that noise coming back so I took the car to garage again. He told he can't figure out clearly and called some mechanic's in BMW and they suggested him that it might because of the electric motor and its chain & camshaft. He advised me not to change it as it will cost a lot and told me to sell the car if possible. Also he told me to unplug the supply going to the electric motor in that way I hear less noise(He warned me that I might not get the usual power). After couple of days when I was driving the car in highway I lost the power and pulled over to the side. It makes squeaky noise when I try to start but it won't.
Also my oil sensor warning was there for few months(orange color) eventhough I changed the oil when I fixed the timing chain. My mechaninc told me it was only the oil sensor malfunctioning. so asked to ignore it for now. Before the car broke down in middle of the road the oil senor turned to red and blinking a lot for that two days. After investing some time in internet trying to figure out if there is any other person with similar noise and I found out it comes from the vanos. It sounds exactly as heard in this video(https://www.youtube.com/watch?v=o5vGmVJT9tE). Some help would be really appreciated if I start with cleaning the vanos unit/replace it myself or is there some serious issue behind it?