I have exactly 370 miles on my new Boxster. Per break-in procedures, I have never exceeded 4200 RPM's. I was cleaning it up a bit and I noticed my exhaust had a fair amount of black residue on it (see picutures).
The car seems to run fine, but based on this residue, I'm wondering if it's running a little rich? There are no warning lights, etc. so I'm wondering if I'm just being paranoid or if this is normal?