Originally Posted by sailingdog
If the odor persists, it is probably because you have mildew or mold in the foam in the cushions themselves, and you will either need to replace the foam or clean them with bleach, to remove the source of the odor.
Windermere, what sort of covering have you got?
If they're vinyl cushions, the mildew/mold won't be in the foam - it'll be on the underside of the fabric. You'll have to take the covers off and get them professionally cleaned (if they don't completely fall apart first like our vinyl cushions did).