Rattling noise coming from the engine

[ju10]

About 2 weeks ago I was driving my car and I began to notice this while I was stopped at a red light.

This is after the car had been leaking coolant for a while.

It has about 170k miles on it

I'll post a video that has the sound:
https://youtu.be/wEVrCMc_4Pc

 

[Samurai_Blue]

could be a loose heat shield. And you could be leaking coolant from a rotted hose.

 

[Petramer]

Maybe the problem is in a tensioner pulley? I think the sound goes from there.

- Peter