FBX Import Problems

Okay So I use AutoCad2012 to create my models. It does a phenomenal job. When I go to export the model as an FXB in unity, the model shows up, but so does ALL the faces that go along with it. All the faces are parented to the actual model, but when I create a big model like a cruise liner, I have over a thousand faces. Any idea’s n how to have the faces not show up?? When I opened the Car Tutorial up and clicked on the car, all the faces were not listed under it…

I have the same prombles, the different is I used the 3DS MAX. When i improted the file to Unity by Max file, the model miss some of the parts. Can anybody give me some help?