Why can the car still drive through the walls?

Hello,

I’m making a simple cargame and I try to fix the collision detection right now. I have kind of fixed so the car slows down when touching walls and if you touch the walls, it rotates with 5. Here is all my code: https://www.dropbox.com/sh/tp50xec8ttfwq38/V90H3dSges. But in some places you still can drive through the walls, why is that? You can run the .swf file and then you will understand better how I mean.

Thanks in advance!