Hot run Problem

[reflex_timberwolf]

I drive a 4.3 tbi sonoma with about 210k on it but it ran like a top and ive done more work to it than im willing to admit. Just the other day it wasn't running right and i got about 2 miles away from my house when it died. I thought it wasnt gettin fuel to i tested the pump(works)changed the filter, checked for spark(sparks good)plugs looked a little s**tty kinda like unburned fuel was running through the cylinder. I cleaned the IAC Valve. It helped a little but not much. I also thought it could be the EGR valve making it run like s**t. but that wouldnt cause it to not run at all since u can block em off and the car still runs... My auto teacher told me to check my coolant temp sensor. Does anyone have any ideas what would make it run cold but not when it heats up?