Mothballs, but not the real ones. 
I might set up a few mouse traps as well this way you'll know if they are around.
Might put rags in the exhaust pipes too to keep them out just remember before starting car.
I might set up a few mouse traps as well this way you'll know if they are around.
Might put rags in the exhaust pipes too to keep them out just remember before starting car.