thanks for the replies thus far - i've already done the carb rebuild - linkages are clean and freely moving, vacuum seems to be in order although i feel like i should go ahead and just replace all the lines - i do not understand the fast idle but it seems irrelevant in a cold start situation - am i wrong about that? i understand that the truck needs to idle high when first started - i ran it all winter and spent many minutes in the driver seat smoking a cigarette waiting for it to get up to temp - but this is not the same thing ... unless i have the idle screw up too high? how many turns out is spec? and no i dont have a tach - i suppose i should order one.