How to troubleshoot engine knocking in my Audi A3?

When driving my Audi A3, I have noticed a strange knocking noise coming from the engine. It usually happens when the engine is cold or when I accelerate quickly. What could be causing this and how can I fix it?

First, check the oil level in your engine. Low oil can cause knocking noises. If the level is low, top it off and see if the noise persists. If not, then the issue may be more serious.

Another possible cause could be a loose or worn-out serpentine belt. If the belt is loose or damaged, it could be causing the knocking noise. Have it inspected and replaced if necessary.

If the noise only happens when the engine is cold, it could be due to a lack of proper lubrication. Consider switching to a different oil or using an oil additive to improve lubrication.