Running the truck with the vac. line off will cause the EGR not to open. If you trace the vac line it will lead you to the Sel. Its actually a simple fix the sel. is held on with 2 bolts/screws and has a set of wires pluged into it. Change it out and your all set. If I were you Id take the EGR Valve back those are a good chunk of change.

 

all changed out tonight. I'll give it a try in the morning.