[aaismaeel]

Hi it's me again.
So I did my routine check on outside garage. I informed them about my Black exhaust pipe although my car doesn’t bring smoke or anything but the pipe is just always too dirty black. They recommend an engine flushing. Has anyone had dirty exhaust problem? what are the common causes from your experience? before I let them start with engine because there might be something else.

[allinon72]

This is common on BMWs and many other vehicles. It doesn't suggest that there's anything wrong, per se, unless there are other symptoms that would lead you to engine problems.