Saltwater stains are white in colour and can look quite unsightly, especially if the upholstery on your car's seats is darker in colour. As with most stains, saltwater stains are easiest to treat when they are fresh and not quite dry. The simplest of mistakes, such as laying a beach towel on your seat to drive home after an afternoon at the ocean, can cause these stains. Since salt stains are water soluble, you will be amazed at how quick and easy removing these stains can be.
Vacuum the stained area well to remove any salt residue.
Re-saturate the stained area with warm water. Use a towel to soak up the water. Repeat until the area is mostly dry.
Inspect the stained area for traces of the saltwater stain. If you can still see the white salt residue, repeat Step 1.
Pour equal parts vinegar and warm water into the spray bottle. Spray the stain generously and let it sit for 20 to 30 minutes. Use a clean towel to blot up the vinegar-and-water solution