Long time no see, I recently discovered a noise going around inside of the engine itself.
I was putting some coolant in my rad and I keep hearing like a quiet noise. Sounds like a little piece of metal or something knocking back and forth on each side of the engine :|

I can't really confirm what it is, but it just sound slike something is knocking around inside the engine. Any clues?

 

Could be the lifters clicking, is your oil pressure and level okay?

 

Pressure and levels are all good.

I had my oil/filter changed about.. 1 month go. I have about 4.5k miles on it since. I recently added some more fluid, figuring the filter might be fine still.

 

Welp I'm out of ideas good luck!

 

What are the chances the lifters might be bad/loose

 

They lifters themselves should fine. If you have low oil pressure or low levels, they could be slightly dry. The noise you get is lifters hitting the cam and the valves

 

Maybe a exhaust leak

 

Or maybe you are just hearing the injectors....