I will check that out. I am replaceing the cam position sensor with the original black one. I got it fron dieselorings.com I hope it fixes the idle. I would imagine that the gray sensor has well over 100,000 miles on it. I just got it going to hook it up later.
Black, Grey, & Dark Blue Cam Position Sensor Perdels Test - Diesel Forum - TheDieselStop.com
Here is the site I got info from may be your idle issue also.