All of a sudden, yesterday while driving home, my 4 turned off, it took me a few minutes to turn it on, and i barely made 100m. It runs irregularly, as if it is not receiving fuel, but it is. Runs for a few meters and stops again, i have to wait a minute and try a few times before it turns on. It has no power but for a second it does and revs go high by themselves, and then shuts off again. Also, i've been told it sounds as if it's running on only 3 cylinders. Any kind of help and advice is welcomed. Thx.