New motor (thanks CCR) in the 87 GL and it won't idle. rough as hell under 1200 and dies will not stay running. Timin seems on and it seems to be a feul issue. Car is new to us so no idea how it was running before the swap past to say that it was running we drove it into the garage but nobody was paying attention to idle speed. We have checked the idle speed screw and even backed off all the way and tried to reset. at seemingly propper timing it will not adjust down to idle speed. anyone have any idea for helping us get this thing to idle? Any help would be great. Thanks

sounds like a vacuum leak