Has anyone experience popping noises from their E60 when driving? The sound is like those little poppers which small kids play with, only more hollow. I have experienced it on my previous 520i and thought the problem would go away when I changed to my current 523i. Shortly after I took delivery, the noise appeared again. Was told by PML to change the brand of petrol I was using (SPC) and the sound went off indeed. Then it came back again last week. Car is at PML now for observation. Also, the OBC started to act up by displaying TRANSMISSION FAULTY msg, had trouble engaging the R gear and the whole car sounded very noisy and was rough to drive. Please advise.