What should I do if my Audi A4's engine is making a strange noise?

I have noticed that my Audi A4's engine is making a strange noise when I accelerate. What could be causing this and what steps should I take to address it?

Firstly, make sure to check your engine oil levels. Low levels can cause strange noises. If that is not the issue, it could be due to a faulty belt or pulley. It's best to have a mechanic take a look at it as soon as possible.

Another possible cause could be a clogged air filter. This can restrict air flow to the engine and result in strange noises. Consider replacing the air filter if it hasn't been changed recently.