91 Buick Century 3.3 Stalling

I have a 1991 Buick Century with a 3.3 V-6, and it stalls, just dies like I
turned the key off. I believe it is an electrical short, or grounding problem.
I have replaced the tps, ox. sensor, ignition mod., electronic ign. switch,
iac valve, knock sensor, plugs,wires, alternator, battery, and computer.
This almost has to be an electrical problem, either loose connection, or a
grounding problem. Has anyone else had this problem. One more queer
thing, the speedometor fails when the check engine lights comes on. Any
ideas? I'm running out of hair.

Welcome to AF!!

Did you change the crank position sensor? Random stalling is a sign of a failing CPS. Based on your description of replaced parts this is where I would start.

Thanks GTP Dad. That was the first thing I replaced. I now have a new
module ordered for my new computer. I am still having far too many odd
happenings. It almost has to be wiring or computer related. "If" I finally
get this solved, I'll let ya know. Again, Thanks.
Confido

On the ignition module and computer, what brand parts did you buy? Cardone branded ECM's are inferior, and I've known people that have gotten 2 and 3 bad ones in a row before finally getting a good one. Same for cheap branded ICM's. Do you have any trouble codes?