I just installed a new wiper motor in my Chevy cavalier the motor works. But when I put the wiper arms back in it doesn't move them. What can cause this problem guys? Thank you!

 

It sounds like either your linkage is not attached, or maybe threads stripped out on the male end.

I'm not sure how the cavaliers wiper arms attach, but I'm assuming the same as most vehicles. 1 nut or clip and they slip over a toothed shaft. If the wiper arm isn't moving, remove it and make sure that your toothed shaft is moving.....if not then move down the line to the linkages, wiper motor, etc.