How can I troubleshoot a rough idle in an Audi 80?

My Audi 80 has been experiencing a rough idle, with the engine stuttering and shaking. I've checked the spark plugs and air filter, but can't seem to fix the issue. What else should I look into?

First and foremost, check for any vacuum leaks in the engine. These can cause a rough idle and are often the culprit. Take your time and thoroughly inspect all vacuum hoses and connections, repairing or replacing any that are damaged or loose.

Another common cause of a rough idle in the Audi 80 is a faulty idle control valve. This component regulates the engine's idle speed and can become clogged or malfunction over time. Consider cleaning or replacing the idle control valve to see if it improves the idle of your car.