Rugs should be brushed or vacuumed regularly to keep gravel and sand from accumulating. If the mats are heavily soiled, remove them, clean or sponge and reinstall, making sure they are dry. Seats and interior trim panels can be kept clean by wiping them with a damp cloth. If the cases become too dirty, use a small amount of liquid detergent and a soft brush to clean them.
When using liquid detergents in the car interior, do not over-moisten the cleaned surfaces. Excessive moisture can seep into the seams and cause stains, bad odors, or even rotting of the fabric. If the interior of your car accidentally gets wet, be sure to dry it properly, especially if it's floor mats. Do not use oil or electric heaters inside the vehicle for this purpose.