truck stalls unless you coast to stop

[kevco420]

if im at a stop idling like in drive threw and i tap gas pedal it will studer and most likely stall.butt if i hit gas then let it coast for a little bit before coming to a stop then it will studer and then maybe the idle will catch and idle smooth.this happens everytime i come to a stop.so i have to remember to let off gas pedal a ways back from stop and coast up to end.its like its not picking up a rolling idle speed to a stopped idle speed quick enough. it is an 1988 350 throttle body.it happens when going reverse then shift to foreward it def stalls.

[amac209]

sounds like a bad tps or iac a restricted exhaust can do the same thing but you'd have little power once it got up to speed. try unhooking the tps(throttle position senson) and see what happens. this will turn on the service engine soon light and put it into limp mode and use the map sensor instead. theres probably a dead spot in the tps. if it stalls after high speeds i'd suspect the lock up clutch solenoid in the torque converter is sticking. good luck with this