Look for a leak, on either the intake or exhaust side of things. Both of these things effect the idle, and often goes away with temperature (leak seals).
I started having erratic idle (mostly slow) on my 04 SEEG. It actually stalled twice on me, while idling at a red light. It never had done this before. I eventually found I had a crack in the rear header pipe. Replacing the pipe returned the idle to the normal 900 rpm +/- 50. In the meantime I had made numerous adjustments that I had to undo once I found the leak. (I can't really take a lot of credit for good detective work in finding the leak...the crack just grew until it became obvious.) Once fixed, everything returned to normal...
Scott