I know this has been posted before. I couldn't find it; so here it goes. When the ac is on high, it works fine, but at any other setting, it dosen't blow anything. Any suggestions?

1999 Contour SE

Sony Xplod 50x4 cd player
APC resonated exhaust tip (just for the cheese factor)

Coming soon:
35% tint done by Madavi's Motor Sports
All new speakers
the loudest muffler I can find