I just bought a 2001 Civic LX Auto and the trunk latch on the inside doesn't seem to work.

It sticks up all the time and when I pull up on it it doesn't have the usual range of motion.

Any ideas on how to DIY fix it?

 

In your trunk, where the trunk's keyhole is, you'll need to pull back the carpet and look at the key cylinder mechanism. Check to see if the cable is still attached to it or if it fell off.