Omega MV6 Speed variations

Hello to each other After the problem with the crooked ZK is fixed and my Ommi is running again the next problem comes now. My Ommi is a 96er 3.0 MV6 Caravan with just 137000 Km on the clock. For a few days the idle speed causes problems after almost every start. Morning and evening, in the cold state the speed fluctuates so that the light becomes darker and brighter again. After about 1.5-2 min it runs normal. Today the phenomenon also occurred in the warm state. It would also be worth noting that the Ommi now needs a few more revolutions to start than before, because it otherwise jumped already shortly after turning the ignition key. I used the SF but found nothing suitable. For a few helpful tips I would be very grateful. With the best regards Lothar