stranded.. what is this and can i still drive it?

[jjzepplin]

And yes. That can cause serious damage if left loose. If the engine was good and hot and backfired just right you could cool a valve too fast and bend the stem and boom-no cylinder compression and a need for your heads to be redone and countless other problems resulting from said bent valve.
As soon as you can check all of the fittings going to your manifolds. And make sure they are good and tight.