I have a 1987 S10 Blazer Tahoe 4x4 2.8L. It starts up fine, but once it warms up a little the idle becomes rough. When i start driving it, it usually stalls out at a stop. If i've been driving for at least 10 minutes and I come to a red light, it will most likely stall out. Then, i just throw it in park and it starts back up again fine. I did a tune- up when I got the truck, so i have replaced:
Spark plugs/wires
Cap and rotor
Fuel filter
Air filter
Starter
Battery
Fuel injectors

When the stalling problem came around, i replaced what was tested to be bad or sounded like the problem:
Timing chain
Ignition switch
Ignition module
Throttle position sensor

I put a junkyard ignition coil, iac valve, egr solenoid, and map sensor on it. The only thing that made a difference was the ignition coil. When i was letting he truck run and shifting through the gears, the truck ran fine. But then i gave the truck a little gas and the problem kicked in.

I'm leaning towards something in the throttle body, since the check engine light gave me the TPS. Any suggestions or questions will be appreciated!

 

Check for vacuum leaks, disconnected vacuum hose maybe. New TPS also Could laso clean the egr valve

 

There aren't any disconnected hoses and all vacuum lines are fine. I have a new TPS and I already cleaned the egr.