93 Pontiac GT dies when brakes applied

I have a 93 Pontiac GT that all of sudden began to experience the problem of killing when the brakes are applied. If you rapidly pump the brakes, the engine will hesitate bad but it'll at least stay running. The killing happens no matter what gear you're in (auto tranny). And, it just started doing it out of the blue. Had driven it home from work one night with no problems, and then the next morning the problem started. I can visually find no loose or bad vacuum hoses. Help!

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Unplug the TCC solenoid connector on top of the transmission and see what happens. It is possible that the solenoid is stuck in the lock-up position and will not release. If that cures the problem you can leave it unplugged but your mileage will suffer.

Unplugged what I believed to be the TCC solenoid, but no affect. I also found an article where a Buick's TCC solenoid failed and the owner was able to disconnect the plug at the brake pedal switch to disable his TCC solenoid. Not knowing if Buicks & Pontiacs have similar systems, I tried that... When I unplugged the small 2-wire plug & applied the brakes, the car didn't die but I had no brake lights & the shifter was locked in place. When I unplugged the large 4-wire pluge & applied the brakes, the car again wanted to die. Further thoughts?

Replace the switch to the brake lights. It appears there is a short in the circuit and is causing the ignition to shut down. Not common but possible especially if you unplugged the switch and the car continued to run. May be a further wiring issue but try the switch first.

Have you tried to apply vacuum to the brake booster with a vacuum pump. If the booster has a leaking diaphragm this would cause a vacuum leak and cause the engine to run to lean and stall. Unmetered airflow. Good luck