Its a common code. i've had it a few times and so have a few people i know. It usually means the egr isnt seating properly. Take off the egr and clean the valve and seat (the exhaust side)with some carb cleaner. Then take the sensor off the vacuum side and shoot some oil in there. I've noticed that the diapham in the egr body sometimes binds thats why I use the oil.
If its really siezed or still binding after this, you'll have to replace the valve.
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