Ferguson got a one-year deal to stay in Minnesota after coming to the Vikings from the Green Bay Packers late in training camp last season. He was second on the team to Bobby Wade with 32 catches for 391 yards and a touchdown.
Wyms is also entering his eighth season and spent last year in Seattle. He'll serve as a primary backup to Kevin Williams and Pat Williams on the interior after the Vikings lost Spencer Johnson in free agency.
Sartz is the second linebacker signed in a week after the Vikings added Derrick Pope from Miami last week.
The former fifth-round pick from Southern California was cut by the Washington Redskins in training camp last year. If he makes the team, it will likely be as a special teamer because the Vikings are set with starters Ben Leber, E.J. Henderson and Chad Greenway.