Why is the engine of my Audi 80 producing a knocking sound?

I've recently noticed a knocking sound coming from the engine of my Audi 80. It seems to occur more frequently when driving at higher speeds. What could be the cause of this and how can I fix it?

The most likely cause of the knocking sound is a problem with the engine's connecting rod bearings. This issue is more common in older Audi 80 models.

Another potential cause could be an issue with the fuel injection system. It may be worth getting this checked by a mechanic to diagnose and fix the problem.

It's important to address this issue as soon as possible to avoid further damage to your engine. You may need to replace the bearings or other engine components.