I have put a new egr valve on truck runs rough on idle.but sometimes it runs with no shaking

It could be a number of things .What kind of difference did the EGR make don't need to answer just big or small .
Their is a part not a sensor on the throttle body called the IAC ideal air control behind the TPS sensor .Its a stepper motor jack screw moves in and out to regulate the amount of air at ideal has a composit rubber seal at the end of the shaft that fits into a seat inside the air horn .The Vcm controls the movement .Carbon build up on the seal or seat will effict the ideal air flow make it run rough at ideal.
You can remove it 2 small bolts and try to clean it but don't push or pull on the shaft it will damage the motor .
Truthfuly I think its a bad disgin to much heat to many varibables to tight tolarances to much expantion and contraction not a good enough seal or control over the system.