94 bonnevile Wiper motor?

Remove wiper motor. You have to remove whole plastic cowl below windshield to see and remove wiper motor.

If the wipers were jammed two things could have happened to the motor. The first possibility is that you striped one of the plastic gears, or the second more likely option is that the ball joint on the wiper has popped off. Try moving the wiper blades back and forth and listen for a sound like metal scraping or dragging which will mean its the ball joint. To fix it first take off the wiper motor and locate the joint still attached to the blades ( move the blades back and forth till you see it). Once you have found the joint tie some rope around the wiper joint arm and pop the joint back together. I had this happen once with a Subaru during a snow storm.