Replaced column with used one in 1999 Chevy Tahoe. Engine cranks but stalls?

Old column had an aftermarket alarm and killswitch. Vehicle was stolen from me and had to replace the column with a used one.I disconnected all the wires to the alarm the went to the column harness from the old one and taped them off.I think that disabled the alarm because I do believe the power was ran through the old column wiring. But I could not track the other end of the killswitch wire. Do you know where these are typically ran aftermarket? Anywho I installed the used column and the car try to start but then stalls out right away. Have no clue whether this kill switch wire is the bproblem or is it that I have to reset some codes for the used and differentg column. Since its cranking its leading me to believe it has nothing to do with the aftermarket alarm or killswitch. Any help plese. Appreciate. Thanx much