i have an 86 4wd with a 22re that i cannot get the idle set on it. i have done as the manual said and i have the set screw all the way in but does no good. whats up?? the idle is too low and it dies especialy when it is cold. could this be distridutor problem? i noticed that it has a vacumm advance on it but is not hooked up could this be part of the trouble?