I can relate to your situation. I too purchased a 2008 4.8i with similar miles two years ago without a warranty and it was of the the worst decisions of my life. Each month there was something wrong with the car. I spent thousands in replacement parts alone in less than a year. I tried working with the dealer but they wouldn't help me at all. They would first give me the run around and then ignored all my calls and emails completely. I then tried contacting BMWNA but they just directed me back to the dealer. I was considering pursuing legal action but I was extremely busy at the time so I just ended up trading it in for my current Tesla. I apologize for not being able to give you any advice but I do wish you the best of luck in resolving your current situation.