I just got my car 3 weeks ago and I noticed that there is a strong odor coming out of the muffler. When the car is parked and I step on the accelerator, I can see black stuff coming out of the muffler. I'm not sure if it's oil or carb deposit. I don't see any indicator light on my dashboard. I really don't know what's going on with this. If anyone can help me solve this problem, I would really appreciate it. Also if you have an idea on how much it would cost to have this fixed.