I have an 07 S550 (W221) w/o 4matic... My fiance was driving the car today and called me in a panic that the car was losing power and also stalled on her a couple of times. The check engine indicator was lit for a couole of hours but now off. She had to stop for gas so i told her to have them check oil, they did and it was a lil low but nothing drastic. When she got home I put my computer on it and got a code for crankshaft position sensor A... My question here is this something I can handle myself? I am great with engines, I have always worked on my own (american) cars but this is the first time I am dealing with a Mercedes. Any help or suggestions greatly appreciated.