How to troubleshoot a Vauxhall Astra's engine knocking issue?

I have noticed that my Vauxhall Astra's engine is making knocking noises. What could be causing this issue and how can I address it?

There are a few potential causes for engine knocking in a Vauxhall Astra. It could be due to a lack of oil or dirty oil, worn out spark plugs, or a problem with the fuel system. I would recommend checking and changing the oil if needed, replacing the spark plugs, and inspecting the fuel system for and clogs or issues.

Another possible cause of engine knocking in a Vauxhall Astra is a faulty timing belt. I would recommend having a mechanic take a look at the timing belt and replacing it if necessary. If the belt is not properly synchronized with the engine, it can cause knocking noises.

It's also possible that the engine knocking in your Vauxhall Astra is due to a problem with the pistons. If the pistons are damaged or worn out, it can cause a knocking sound when the engine is running. I would suggest having a mechanic inspect the pistons and replace them if needed.