Chevrolet Repair: 1996 Chevy S-10 Blazer 4x4 4.3, fuse panels, vacuum line

Question
I have a 1996 Chevy S-10 Blazer 4x4 with a 4.3 vortec and when I turn the ignition key to the off position the engine stays running.  I have bypassed the ignition switch and ECM by unplugging each with the key in the off position but not running and the lights stay on in the dash.  The only way to shut the motor down is to kill the main power source.  Have you came across this before or do you have anything that can help me out.  I appreciate any information, Thanks!

Answer
You physically climbed under the dash and unplugged the multi-wire electrical connector from the ignition switch mounted on the steering column and the car still runs ?.


Did you physically remove and test each and every fuse in the fuse panels ?.


What mechanical work or ANY kind of work has been performed on the vehicle recently ?. As most problems that occur after a recent repair was made can be traced back to the area of where the repair was made as a vacuum line may have been knocked loose or a wire connection came loose, Look around in the area where work was performed..