I have a 94 GMC 1/2 ton P/U 350 cu. in. engine
When truck is cold runs great, once warmed up to 180 degrees, stumbles and hesitates on acceleration, really noticeable between 25 -45 mph. constant miss, lost of power, sluggish.
I've replaced MAP sensor, EGR soleniode, checked and cleaned EGR valve, spark plugs, spark plug wires, distributor, distributor cap, rotor, water temp.sensor, fuel pressure regulator in TB, ICM twice, reset timing to 0 degress TDC, scan for codes.
no computer codes, no check engine light.
What are your thoughts.