My wife`s truck ...
fairly recent fuel pump and filter
has error code for EGR valve
good battery and charging at 14 volts
350 gas motor

I`m going to replace EGR valve, but still want some advice from experienced peeps.
Recent lower intake manifold gaskets installed and was running pretty decent, but now running rough.

-truck starts right up and idles
-in neutral, engine revs up with accelerator
-in drive, the engine won`t rev higher than 1500, maybe 2000 rpm
-if you feather the gas pedal, you can get her to go
-if you give too much gas pedal, it stumbles and gives little backfire coughs but does not die easily

Your advice and experiences are appreciated Thanks -Dave