1994 Plymouth Voyager occasionally stalls

1994 Plymouth Voyager mileage: 88,000. What can cause this auto to occasionally stall out? Sometime it can be restarted immediately other times it will require a 10 to 30 minute before a restart can be accomplished. These stall occur at random and no specific period can be established. About 1 month ago, the fuel filter was cleaned or replaced and that appeared to correct the problem but only temporarily. Thank you for whatever advice you can provide.