Hello Scotty, I have a 94 Chevy Silverado 2wd,350 5.7 automatic transmission that I'm having problems with , at first I was getting codes left and right. So I took it to my mechanic cause my truck will hesitate at times , low idle, or sometime would even stall on park and sometimes when I turn on the AC and other times on change of gears or at stop sign/light. I've changed the IAC, TPS , checked injectors/gaskets , changed fuel filter, and also my mechanic said that the PCM was going bad so I also replaced that, new wiring for spark plugs and new spark plugs as well with rotor and distrubitor.
. But the truck is still doing the same thing please help cause I have ran out of clues Thank you in advance

that's the problem with those pre obd II vehicles, very little data can be had from a computer scan. But you can't really "check" the injectors and that's the main thing that wears out on those old things. Me, I'd try a set of rebuilt injectors

You are right , but I was trying to say like if the rubber parts where like wore out but I'll try that hope it works