Been a Audi fan for a longtime since my first one a Audi 80 in 1985 and had several more since , but I had for a few years wanted a A2 which I have finally managed to get . It's a 2005 se with full Audi service history 1.4 petrol 83000 miles but only after having it a few days it has started to make a knocking noise from the engine like a tappet I'm not sure if after reading the posts on here if it's not to happy with cheaper supermarket petrol?