Mitsubishi Repair: bucking stalling suffocating warm, coolant temperature sensor, radiator stop leak

Question
1992 mitsubishi libero 1.8 auto. Applied bronze radiator stop leak powder per spec and problem began immediately. Only begins when engine reaches half temp. Rolling idle fine but low speed or strain on accelerator suffocates. Had to keep pumping pedal to get home. Similar to MAF sensor issue i had before, more erratic/difficult. Sensor of some kind? Help much appreciated!

Answer
Jay,
There is a engine coolant temperature sensor that you car's computer (ECU) uses to determine it's temperature.  This temperature reading is used (among other things) to help the ECU known when to turn the fans on/off, regulate air/fuel mixture, and regulate idle speed.  You should start with checking that sensor.  It may not be what's causing your overall problem, but it's a start.
Good luck!