How do I know if my Audi A2's engine needs a tune-up?

I recently bought a used Audi A2 with high mileage, and I want to make sure the engine is in good shape. Is there any way to check if it needs a tune-up without taking it to a mechanic?

An engine tune-up usually involves replacing spark plugs, cleaning or replacing the air filter, and checking and adjusting the ignition timing.

You can check the condition of the spark plugs and air filter yourself. If they are dirty or worn out, then it's a sign that your engine might need a tune-up.