How can I diagnose engine idling issues in my Audi 80?

I have noticed that my Audi 80 has been idling rough and sometimes stalling. I am not sure what could be causing this issue and I would like some tips on how to diagnose and fix it.

First, check for any vacuum leaks using a vacuum gauge. This could be a common cause of rough idling in many cars, including the Audi 80.

Inspect your spark plugs for fouling or wear and replace if necessary. Faulty spark plugs can also contribute to rough idling and stalling.

Check the fuel pressure and ensure that the filter is not clogged. Low fuel pressure or a clogged filter can cause issues with idling and stalling.