How can I troubleshoot cooling system issues in my Audi?

My Audi seems to be running hotter than usual and I'm noticing some abnormal noises when the engine is running. What could be causing this issue and what steps can I take to diagnose and fix it?

Start by checking the coolant levels and making sure they are at the proper level. If they are low, you may have a leak in the system that needs to be addressed. It's also important to check the condition of the coolant and make sure it is not contaminated.