01 mustang question

[imthehink]

What is this wire? It looks to be a ground of some sort. Any help would be great. Thanks http://s84.photobucket.com/albums/k13/imthehink/?action=view&current=S5031828.jpg

 

[89Daytona]

It looks like an engine ground wire.

 

[imthehink]

it grounds to the firewall. The body shop forgot to bolt it back. Thanks