Well not sure if you renumbered it prior to remove the stacking cables. I faced an issue like this long back (not remembering it clearly). But what i followed was
1) Disconnect the stacking cables
2) Renumbered the switch with the command switch 4 renumber 1
3) Then i issued the command no switch 4 provision
Better do this on a proper change window.
Also, could you please provide me the output of show switch neighbors
Thanks
Vivek