If the car mat has salt stains, dissolving 50% of vinegar and 50% water is useful. Vinegar has the capacity to rinse off old stains. Put the mixture in a spray bottle and fetch a towel and a bucket to start cleaning.
So, remove the car mat and put it on the floor or on a waist-high stand. Spray the mat in the areas that have stains. Do so for 2 or 3 minutes until they are all covered with the solution. Then, let the mixture soak for 3 minutes and rub the mat thoroughly with a towel. Vinegar will have an effect on the crystalized salt. After that, use paper towels or a vacuum cleaner for drying the mats.
Additionally, you can dampen a rag with the solution and rub it all over the mat, vacuum-clean, and finally dry with a paper towel or just leave it to air dry.
An alternative worthy of consideration is also using steam to dissolve stains. Since steam is hot, it breaks down the crystalized salt much easier. This method is recommended for car mats with many salt marks. Steam not only acts as a power cleaner but also as sanitizer for the seats of the car. In the end, it will leave the air fresher inside.
The other options are shampoo + water. Shampoo is great for weakening crystalized salt, so you can use either shampoo or vinegar for those stubborn marks. Remember to use a dampened towel to wipe away the shampoo when done.
James Watson is a staff writer at serebii.info, where he covers tools, home improvement, and outdoors. Previously, he was an editor at Popular Science, where he wrote about technology, science, and gaming. He does a lot of DIY projects and has a Ph.D. in creative writing.