Why does my Audi A1 engine make a rattling noise at idle?

I've noticed that my Audi A1's engine makes a strange rattle noise when it's idling. It seems to go away when I accelerate, but it's definitely noticeable at low speeds. What could be causing this and how can I fix it?

The most common cause for an engine rattling noise at idle is a problem with the timing chain. It may be loose or worn out, causing it to rattle against other engine components. It's important to have this checked and replaced if necessary, as a broken timing chain can cause serious engine damage.

Another possible cause for the rattling noise could be a faulty exhaust system. Over time, the exhaust pipes and connectors can become loose, causing them to vibrate and produce a rattling noise. Have a mechanic inspect your exhaust system to see if any parts need to be tightened or replaced.