I've been searching through all the old topics but this seems to be a new one...

I was driving down the highway last night and looked at my Edge Attitude, it read and engine temp of 417. I immediately looked at the coolant temperature gauge on the dash and it read perfectly normal. I didn't notice any change in the sound or performance of the engine up until this point. Well, I stop to get fuel and when I go to turn the truck back on, the wait to start light stays on (I didn't wait for it to turn off considering the engine was already warm) and now when I start the truck, it is considerably "rougher" idling and about 100 rpms greater, and the wait to start light seems to be on constantly until I start it. I wait about 10-15 seconds while it is idling and the rpms drop and the roughness disappears. I am totally stumped and so was the dealer that I spoke to on the phone. The truck is an '04 with an LB7. I am thinking it is some sort of sensor or relay that has nothing to do with the dash gauge, but has something to do with the glow plugs and the edge reading, but really I'm not sure. Any help would be greatly appreciated. Also, will it hurt it to keep using the truck even though there is something definitely wrong with it?
Oh yeah, I forgot to mention, I disconnected the Edge and it is still doing the same thing.

Thanks guys,
Brent

Well, after thinking it over, I opted to just take it into the dealer and let them handle the whole thing. I will post what was wrong for others to know if they run into the same thing.