as far as i am aware it the same with a L6 ecu,have u cleaned out the iscv ??might just need a clean,before trying to set the idle?

to set the base idle get the engine nice and warm disconnect the iscv under the throttle body u will see the nut 13mm i think undo this and ajust the screw untill she at around 850rpm then lock the nut again and reconnect the valve idle should not change in the slightest when u reconnect if all ok