After idling 10 mins more car would make rattling noise

Hello,

Typically rattling noise comes from loose components.
One of the most common cause for rattling noise is a loose exhaust manifold shield.

If you can upload a video when you hear the noise, it can be helpful determining what might be causing it.

Here is a helpful guide of different engine noises:

https://www.2carpros.com/articles/engine-noises

Go thru this guide and let me know of any questions.
Thank you.