Pet accidents, red wine, tomato sauce or coffee stains can be notoriously difficult to completely clean up after a spill. Removing these stains from carpet or upholstery, especially stains that have set in over time and keep returning to the surface, can be frustrating. A reappearing stain, called "wicking," may get removed from the surface with traditional cleaning methods, but not from the carpeting or upholstery padding underneath. Recurrent stains are usually not permanent, however, and can be removed with a gentle, wet solution.
Make a cleaning solution by filling a bucket 3/4 full with water. Add a small amount, less than a teaspoon, of liquid dishwashing soap. Mix in the soap to create light suds.
Carefully pour the cleaning mixture onto the stained area, being certain not to oversaturate. Make sure to cover the entire area of the stain and about an inch outside of it. Allow the solution to soak in for a few minutes.
Using a white cloth or towel, depending on the size of the stain, gently rub the area back and forth or in a circular motion so the water-based cleaning mixture covers the entire stain. Do not scrub the area. Vigorous scrubbing could damage your carpet or upholstery.
Using a dry section of the cloth or towel, or clean paper towels, begin to soak up the wet area by pressing down on the carpet or upholstery. Sometimes this is done best by standing on the area. This action should help extract the staining liquid deep from within the padding, bringing it to the surface into the cloth or towels and at the same time beginning the drying process. Repeat this several times as needed.
Remove the towels from the area, turn on the shop-vac and continue extracting the cleaning solution and stain from the carpet or upholstery with the vacuum. The shop-vac will provide extra strength to the extraction process. Continue this as long as you are seeing improvement to the stain and the area begins to dry.
Repeat this entire process as needed until the stain stops returning. It may take several attempts to remove all of the staining liquid from deep in the carpet or upholstery.