HELP! 3.4 rattling noise, low idle..

So had a faulty fuel injector o ring that I was replacing.
Put the truck back together, started it and noticed it had a low idle and was making a pretty bad knocking/ratting noise.

Almost sounds as if something is rattling around inside the engine but I'm positive I didn't drop any bolts or tools into the engine.
Friend that was helping said he didn't either.

Anthony250f said it might be a loose spark plug wire or spark plug

Posting a video soon, if anyone has any suggestions that'd be really appreciated!

 

How much alcohol was involved during this?

Video would help. It could be anything without a better description.

 

Well the problem just took care of itself somehow... let it idle for a few minutes and the noise went away...
miraculously no alcohol was involved.