Whys my car dying when im driving and i come to a stop?

back in the early days, gm had issues with the torque converter solenoid not releasing the converter when downshifting causing the issue you have. a quick check is to disconnect the square connector on the trans facing the front of the car on the drivers side. if the problem goes away, you need a trans shop to help you out. if it persists, then you have other issues with the motor. Roy