My XJ will not turn off !

I just picked up a '94 over the weekend and it will crank fine, but it will not shut off. I replaced the ignition switch (on the column) it worked great about 1/2 dozen times and now it is acting up again. I suspect there is something broke where the rod attaches to the tumbler, but I can't find any good info or illustrations. I have searched several of the popular part suppliers online but I can't find anything there either.

Any suggestions would be greatly appreciated.

Thanks from a newbie (both XJ and off roading)

Look under the dash and make sure the rod is moving completely. If it's moving the switch back correctly then that's not the problem.

I've actually had this problem before.. Turned out to be a shorted computer. Swapped the computer for a spare and it worked properly.