i know the shaft on my 4 barrel roch. carb should be tight and not leaking vac. but is there any amount of play thats OK? i read to spray wd-40 on the shaft around where it enters the carb and if it changes the idle its faulty or worn out. when i triied to jiggle mine i could only move it in and out a little but it makes a click when i do it and i also have to open the throttle pretty much all the way to do it. i sprayed the sh*t out of both sides and i never noticed any difference in my idle, so does that mean mine is hunky dory? altho when i sprayed it right inside the carb it seems to raise the idle and smoothen out a bit, but thats a whole other story tho...