Chevrolet: intermitant stalling, coolant temp, starter troubles

Question
i have a 91 chevy k 1500 pick up. when motor reachs operating temp it sometimes just shuts off. is starts back up and runs fine for a couple of days or you could go a couple of feet and shuts back off also you could go weeks and no problem. i have changed gas filter , map sensor , tps sensor, eletronic spark controle module , throttle positing sensor, and coolant temp sensor.i also have had it scaned and no codes apear. friend let me borrow scaner to keep it pluged in and no problens found. all though it seams it takes about 3 to 4 days for it to act up after above sensors were changed . any suggetions or is there something i over looked .  

Answer
CAL ;
 HI - well the only thing I can think of if you get no codes , is the ing. switch could be acting up . it could be grounding  out / or shorting out, . You have no starter troubles right , if yes than it could be the fields in the selinoid .