As I answered you before, please use the GTA SA Modding Section for that. I explained you how to make TXD's but you made a mistake, first you'll need to get 3ds Max to put the textures in model and save the car DFF with KAMS's GTA script tools to make DFF's and COL's. Then after that get G-TXD (Google it) and create a new texture file. About the crash, it's not just model and you're there, you'll need to apply car characteristics, like lightning place, driving, etc. I suggest you to google some tutorials because I only model buildings.