![Surprised :o](./images/smilies/shocked.gif)
Avtar- apparantly your car has something called the S1CBA option- cunningly listed as 'CO2 equipment'.
I found the part trawling real oem here
I may be totally wrong, but I'm guessing it's to do with getting the early SDs into the emmissions band.
IIRC Squaky2's car is a bit newer than yours but did not have them- BMW must have worked out a way to reduce the emmissions through ECU reprogramming and/ or small engine mods by then.
I couldn't find any further info googling the S1CBA code- others may have better luck. Hopefully mystery now solved!
![Smile :)](./images/smilies/original.gif)