[rdorman]

Oh... and clean the fast idle linkage (if any) and the secondary throttle plate. Also check that the 'closer link', for lack of a better word, is bent just right so that is touching the slot and fully closes the secondaries. Sometimes the springs are really like in vacuum secondaries and that combined with a little dirt or interference will hang them a bit. Eleminate a linkage problem by disconnecting it and rev the engine a bit manually and see if it returns to the proper idle. You can also manually 'rev' the secondaries at the same time and note the results.