Why is my Audi 80 engine making a rattling noise while idling?

I have noticed that my Audi 80's engine makes a loud rattling noise when the car is idling. It seems to go away when I start driving. What could be causing this issue and how can I fix it?

It is possible that the noise is coming from a loose or damaged heat shield under your car's hood. Check for any loose bolts or visible damage and have it repaired if necessary. This should greatly reduce the rattling noise.

Another possible cause for the rattling noise could be a worn-out timing belt or tensioner. It is important to have these components checked and replaced if needed to prevent further damage to your engine.