Option 1:
Have you seen those people on bicycle selling Chuha Maar things. The medicine by touch and look is like a hard jelly. Place it in your car at different places. When the mouse will eat it, it will have to run in search of water to drink. So you will either have to leave the cars door open or you will have the rat dead under the seats or the carpet. So you will definitely get rid of the mouse.
Option 2:
There is a gel for killing mouse available in the market that looks just like glue. Dont know the exact name but its very common. Take a piece of cardboard about 6''X6'' and apply the gel on it by spreading it on the cardboard. Now place the cardboard on the floor of the car. Remember you dont have to leave the doors open. When you will come in the morning, InshaAllah the mouse will be stuck to the gel as the gel smells like rat food but it is glue. Now lift the cardboard and throw it out.