There is so much on this on the web I have totally confused myself. My car (B230E engine) idles at a fraction over 1000rpm. I don't think there is a fault as it is rock steady and idles smoothly, hot or cold, and starts perfectly.
From what I have read it ought to be idling at about 750-800rpm. From reading it appears that adjusting the idle involves more than just twiddling an adjustment screw, but then most of what I have read involves US spec cars with a different system to mine. I have the CI system with no complicated black boxes to mess up (according to the Haynes manual).
Is this a job best left to a garage who have gas analysis equipment.
Bill UK