From memory the heads are all the but the sensors can vary. If it is over fueling, from memory and dont quote me on this it's been a long time but there's a screw on the back of the underside of the top of the metering head where red fuels line come off that came be adjusted. There is also a sensor on the left landslide as you look at it that get shity and fail although becareful as I think there are to types. Im sure ive got a manual on the ke jetronic system I'll try and dig it out for you. I changed it efi in the end on my s2. Mfi is great when I works but a ball ache when it goes wrong.