How do I troubleshoot rough idling in my Audi 80?

I recently bought a used Audi 80 and have noticed some instances of rough idling. It mainly occurs when the car has been sitting for a while or during initial start-up. What could be causing this and how can I address it?

Rough idling is a common issue in older Audi 80 models and can be caused by a variety of factors. First, check your spark plugs and replace them if necessary as this is a common culprit. You should also check your air filter and clean or replace it if needed. If these do not solve the issue, it may be due to a dirty or malfunctioning fuel injector. Consider getting a professional cleaning or replacement to fix the issue.

If your Audi 80 is equipped with a carburetor, rough idling could be caused by a dirty carburetor that is not able to properly mix air and fuel. You can try cleaning it with carburetor cleaner or have a professional do it for you. Also, check your vacuum lines for any cracks or leaks as they can also contribute to rough idling.