I am working on a car game and I am trying to stimulate a bang effect when the player car bang onto an AI car, the AI car will just get bang away. I am using ent_move for the car AI.

Whats the question? There is a good resource on the wiki that provides code for making dents in the model and making sound upon impact. Is that what you are asking for? Here is the link: Car Physics with many cars

Thanks Volund the problem is solve but my problem was to use physics together with the c_move. At first, I didn't get it to work but after some research I manage to get the AI car with physics and c_move in it.