Hey guys, I'm having problems with my '89 Silverado 1500. Starts and idles fine, after driving a bit truck will loose power like it's not running on all cylinders have to pump the throttle or mash it to the ground to get it to come out of it. At a stop sometimes I have to keep the engine from dying, sometimes it will idle fine. Fuel pump is almost two years old, I feel like the problem could be as simple as spark plugs and wires? Could be the coil? Could be Distributor?? Let me know what you guys think, any and all info is appreciated. I'll try and answer your questions best I can. Thanks

 

Almost sounds EGR related. Try unplugging the vacuum line at the EGR and disconnecting the electrical connector on the EGR solenoid. It'll trip a check engine light when you drive around in overdrive for a chunk of time, otherwise if you're going less than 45mph around town, then no CEL.

Mine runs like gang busters with the EGR unplugged, versus when it is plugged in.