What are the common issues with Audi A4's turbocharger system?

I am planning on buying a used Audi A4, but I have heard that the turbocharger systems in these cars can be problematic. What are some common issues that I should watch out for? Are there any specific models or years that have known issues?

The most common issue with the Audi A4's turbocharger system is oil leaks, which can lead to major engine damage if not addressed promptly. This is often caused by a faulty oil seal or worn-out gaskets. It is important to regularly check for any signs of oil leaks and to have them fixed immediately to avoid expensive repairs.

Another common issue with the Audi A4's turbocharger is turbo lag, which is a delay in acceleration when stepping on the gas pedal. This can be caused by a variety of factors, such as a faulty wastegate or clogged catalytic converter. It is recommended to have a professional mechanic inspect the turbocharger and exhaust system if you experience this issue.