My 2004 Honda civic is making a noise behind the dash! I think it's the blower motor. It will only turn on when you hit it and now the problem has gone on for so long that it's barely blowing any air at all. Can someone please help me figure out what I need to do to fix this?

 

Mine had leaves in the fan cage. One day it was all good, then it sounded like a card in a bicycle spoke, then it barely blew air at all. Pop it out and see if there is anything blocking it.
If it doesn't turn well you can try some 3in1 oil, just a couple drops in the bottom bearing and work it in, maybe a couple more drops and let it sit a bit to soak in.
Mine works great now, I hope you have a simple problem also.

 

Depending on how much the blower motor is used I would suggest replacing it with a new one if the noise is too bad. That is pending there isnt any trash in the cage. Mice and other small animals have been known to make nests in there and then they throw the balance of the blower off and that can lead to failed bearings just make sure the cage isnt stuffed and if it is check the freeplay in the bearing if it seems too loose then replace otherwise you can just clean the cage and reinstall it

 

+1, it's real simple to drop the motor and check for mouse nests or bad bearings. Unplug the wire, remove the 3 screws holding the flange part onto the duct.