1996 Chevy S-10 Engine Stall

I own a '96 Chevrolet S-10. I have never had any problems to speak of, but over the last several months my truck will stall from time to time when accelerating or after I haven't driven it in a couple of days. I have taken it to a mechanic, but the problem hasn't been resolved. He replaced the fuel pump once (it needed it anyway), but that didn't resolve the problem. I took it back to him in February, and he thought it might be a loose sparkplug, but that hasn't worked either. I have tried fuel injector cleaner, and that hasn't worked, but I have read forums and people say that I might should clean the throttle plate. Is that sound advice? I don't really know what else to do or who to ask, so any advice would be greatly appreciated. Thank you.