Here is the latest on the SES issue I was having. The light came back on after a while and I decided not to reset it. Took the car in to the dealer yesterday and got the car back on the same day. It turns out that my scan reader was correct. It was indeed a faulty knock sensor that was causing the SES to come on. I didn't even mention to my service adviser that I had scan the X3 with the OBDII scan tool nor that I had reset it in previous occasions, just to see if they were going to come up with some other BS. But surely enough, they found the problem and fixed it right on the first time. I hope this thread helps others having this type of problem. A relatively new knock sensor failling intermittently!!???? YES, IT HAPPENS!!!!