stepper motors missing steps

Recently i have found a text about using the controller of a disk
drive and use the included stepper motor from the parallel port
I connect everything (i have 2 5,25" teac drives) first i tried the
mastercontrol ez cnc free software but all i get is some jerky
movement (just by opening the program) and vibration,then i tried
turbocnc there everything seems to work fine i jog them cw ccw no
problem until i realized that if i use the go to (g) command to some
point and then return to the original position ther some steps
missing if sent it to some distance it rotates well for two rounds
then vibrate loose some steps and then for the last rounds it looks
ok,also if run a dnc file that after a few small movements return to
the original point, but it never returns.
Please help, somebody, this is my first try i want to build an
engraver.