Why does my Audi 80' engine make a knocking noise?

My Audi 80's engine has recently started making a loud knocking noise while running. It seems to be coming from the engine itself and it's quite concerning. What could be causing this and how should I address it?

The knocking noise could indicate an issue with your engine's bearings. It's important to have this checked by a mechanic as soon as possible to prevent any further damage.

Another possible cause could be a problem with the timing chain or tensioner. This could also lead to more serious engine issues if left unaddressed.