EGR Valve keeps burning out 98 navigator
 

So my navigator keeps shutting off when it is idle or coming to a stop. once it burns out the EGR valve burns out. I changed the vacuum solenoid valve and changed one of the hose that connects to it that looked old/damaged. it continues to shut off. Went to the junk yard for countless EGR valves to change after each shut off but i need to figure out a solution. Anyone have any ideas or know what it could be? any help would seriously be appreciated.

Can you provide the year, engine and mileage?