I have a 1990 w250 4x4 with a throttle body 318 that is being a little cranky. In the last couple weeks it hasn't wanted to idle at cold start. Starts like a carbed engine with no choke. I have to give it a little gas to keep it idling. It runs ok down the road but when you come to a stop sometimes it idles ok but other times it idles way to fast. I gave it a quick look the other day and all the vacuum lines look ok. Any body have any ideas what might cause this kind of problem?