I had a problem very similar to this and it turned out to be a vacuum leak due the hoses going to the ICV being completely melted. I should have taken pictures because it was amazing to me to see the condition of the hoses. I have an '01 X5 4.4. These hoses are easy to see if you remove the plastic engine cover and look towards the back. Hope this is helpful somewhat. By the way, my check engine light came on and went back off.

__________________
Tracy
2005 Imola Red X5 4.4
1995 Daytona Violet M3
"Girls Go Fast Too"