I was just reading another BMW post Red Oil Pressure Light - E46Fanatics and someone suggested that increasing idle rpms may help and 500 rpms is too low. I have around 500-600 without AC. The picture of OBD scanner I posted earlier was with AC on (700 rpms). It seems strange that I have worn bearings with only 100k miles on engine - is it common for M62 engine? Is there any other symptoms of worn bearings other than low oil pressure? If I take to someone to check oil pressure with gauge - what is it supposed to be? and at what rpms exactly?

P.S.: When I picked up car from seller he said it was sitting for 1 year, and he supposedly replaced oil before I picked it up, but he suggested to do it again because it was very nasty when he did it. Also on my way home on the highway - I did not notice any oil pressure lights, however I would assume it was enough (10 mile trip) to make engine hot. After that I had a few very short trips which probably were not enough to make engine hot. I noticed the issue with low oil pressure light after I left key in ignition inserted and it drained battery quickly. It had to be jumped. After that I tried to drive it some more to get battery charged and noticed the issue at the light after driving about 6 miles (driving hard in Sport). I am not sure if it can be related or not... Also initially when I saw oil pressure light I thought about oil leak and I added 1/2 quart of oil twice - it gave me another 3 miles range each time until oil light started flickering again at stops. After that I changed oil + filter + oil pressure switch.