I have a strange idle issue that I cant seem to find someone else having. My car starts and idles fine for around 2-3 minutes. Then it will start to surge and want to stall. Suddenly the cel comes on and it clears up and idles at 850 fairly smoothly. Also on warmed up restarts it will surge for a minute or so then throws a cel and idles normal. What could this be? Could it be my egr delete?