I have a 91 Silverado 350 5 spd TBI. The truck stumbles, studders, kicks and just plain wont run until it gets up to temp. I have replaced the following with no improvement

fuel filter 2 times
egr valve
temp sensor
throttle position sensor
idle air control valve
rotor button
rotor cap
plugs
wires

the plugs have been removed and checked and show a good clean burn. Even after replacing the idle air control valve, when the elec lead is pulled there is no change in motor speed up or down. Manualy pressing the egr valve causes the motor to stall.

Any ideas would be greatly appreciated
Thanks in advance

 

the only other things i can think of that arnt on your list would be the feul pump or the injectors maby a can of injector cleaner? cant hurt to try and its cheap!

 

I forgot that, I have used numerous fuel injector cleaners. I am trying to locate a dealer for 44K.