AUDI jerks as long as it’s cold

Hi, hope you can help me! I bought my AUDI 80 again in the spring – after I had to scrap my first one because of a BMW driver… Well my problem: When I start the Audi and run a piece in idle mode or if I have to go and stop again after a few meters, it happens that it goes out again. And as long as the engine is cold, you sometimes have the feeling that it doesn’t want to take a gas and then it goes again after a ruffle. Is an Audi 80, B4, B ausjahr 3/1994, 2.0l, 90hp, engine identification letter: ABT