I bought a 98 lumina a while back and today i tried to use my wipers and only the driver one worked, and now both dont work. I can hear the moter running but the blades try to move but dont.

Im thinking they skipped over a tooth? Or broke one off? I have no idea.

 

Could be a loose nut. try taking off the cover at the base of the wiper arm and tightening the hold-down nut.

 

my truck had the same problem, i had to replace the wiper motor, it was like $50

 

loose nut like stated above