I also purchased a C230 Komp about two months ago--my impression is the same. Very noisy, especially on cold mornings. Everything I've read indicates this is normal. It's a shame, but a guy in the MB service department told me that when they first got a CLK (with the same engine) on the lot they thought it had an exhaust leak! Rather unrefined, but at least the performance is simillar to the six cylinder at about $5,000 down market. I would be happy to talk further with you.