Why is the engine of my 2018 Audi A4 making a rattling noise?

I recently purchased a 2018 Audi A4 and I've noticed a rattling noise coming from the engine. It's not loud, but it's noticeable when idling or driving at low speeds. What could be causing this issue and how can I fix it?

It is possible that the noise could be caused by a loose or damaged belt in the engine. It is recommended to have a mechanic inspect and potentially replace any damaged belts.

Another possible cause could be a faulty pulley or tensioner in the engine. It's important to have these components checked and replaced if necessary to avoid further damage and potential breakdowns.

Oil or other fluids may be low or dirty, causing the rattling noise. Check your oil and fluid levels regularly and change them according to your vehicle's recommended maintenance schedule.