Water leak on 2005 Chevy Cobalt

The plastic drain tube that runs down your A pillar from your sunroof is attached to the sunroof assembly by a little rubber tube that's just pressed on. Over time they shrink or otherwise work their way loose. If you pull your plastic A pillar trim, remove the sun visor and gently pull your headliner down a bit in that corner you should have access to it. Push it back on the drain tube and secure it with a tie.