Weird Cable Hanging in my engine

[vicsantana91]

Hey guys so as I was checking my oil levels I saw this cable hanging under the main fuse block and the power steering fuid resevoir. I took some pictures of it that way you can tell me what to do with it. My truck start and runs fine but sometimes idles at high rpms does that have to do with this?





By the way I forgot to mention that it has a harness the comes form under the fusebox



and then I saw this cable which I follow and goes to the spark plug cables