Sounds like your EGR Valve pintle may be stuck open, possibly due to carbon buildup, or it may have went bad.
Before you remove it to check it to be sure the 5v reference wire has voltage, and that the ground is good, also check to see if there is voltage on the control circuit, give the car a little gas and see if the voltage increases, and decreases as you let off of the gas.
I am trying to find a wiring diagram for you, but am having a little trouble doing so, I'll keep looking though, hopefully somebody else will post up a diagram if I cannot find one.
If you want to go ahead and check the pintle before checking the wiring, you can do so, just get you another EGR Gasket, remove the EGR Valve and inspect the pintle for carbon buildup, if it is dirty clean it up.
You can take something like a small metal rod, or something similar, and push in on the pintle, watch to see if it sticks open while doing so, it move freely as you push down on it, and release it, if it does not then clean it, and put it back on with a new gasket.
Also check to see that the solenoid works, here is a link to help you do that.
EGR solenoid test
Still have not found a wiring diagram, well I did find one, but it is in a video, this is for another code, but the wiring diagram info is good.
You can see the diagram around 2 minute mark.
I'll still try to find a better diagram if I can.