Search forum for the Bosch p/n for the crankshaft sensor and go by local M/B dealer to get one. Don't worry about the camshaft one for now. If they are so smug as to ask what car it's being used in, just say 2004 SLK320. Quickest way I know how to get one. Also, you didn't give an answer about your battery. If you still have the white Varta, replace it immediately. Like it's been stated, it doesn't matter if it's "Reading Fine". It's a 9 yr old battery. My wing started rising upon car start, but battery was "fine". One week later and doornail dead.