wiper trouble

94 lumana apv the wipers have been acting up for a long time. They would go up and stop I could hit a bump and they would go down. Now all they do is go up. I have to push them down and they will go right up but thats all . I can hear the motor running but they wont ever go down unless I give em a shove. Any thing someone could do to help me would be great! any ideas?

I think you are not talking the classic wiper sydrome...there are lots of references to i this forum.
http://www.automotiveforums.com/vbulletin/showthread.php?t=512424

So if you hear the motor running, then most probably this is a mechanical problem: either loose shaft or stripped gear inside. Remove motor using same instructions above.