Dish detergent, vinegar, baking soda and glass cleaner can all be used to clean most car upholstery. Stained leather upholstery can be cleaned using a soft cloth and leather cleaner.
To clean vinyl upholstery, sprinkle baking soda onto the area and scrub it gently with a damp cloth. Rinse the baking soda with water that contains a few drops of liquid dish detergent, and allow the area to air dry. If mold is present on vinyl seats, spray the interior of the car with undiluted white vinegar, then scrub the upholstery with baking soda to remove the stains.
To remove difficult stains from cloth upholstery, pour a small amount of cold water over the stained area to dilute any spilled liquids, and press a dry towel over the area to remove the excess moisture. If the stain persists, spray the area with commercial glass cleaner. Use a wet vac to remove any remaining moisture, or blot the area dry with a towel.
To clean grease stains, sprinkle a liberal amount of cornmeal and salt over the stain. Allow the mixture to remain on the area overnight. To clean spills on leather upholstery, wipe the area with a damp towel and dry it immediately.