My ctd Idles kinda funny, in the morning it makes some abnormal sounds out the straight pipe, more the colder, never does it after i put it in gear. has complete new fuel system (ouch, I think my dealer screwed me) anyways is this normal or is theer somethin up? has done it for a long time, even before teh fuel system replacement.

 

I know the Quad boxes have had some little issues like that. I am not saying that is what it is, but you might try and remove it then see if the truck still does it.

 

My 05 does it. It sounds like a gas rig with a little lopey cam in it.. Mine only does it in the cold mornings.. Is it the grid heater cycling?? I think it is normal..

 

try cycling the key 2 times when cold out...
1,turn key on let the grid lite go out,turn key OFF,count to 10 turn key on
and let the grid lite go out...then start the truck this works for me when cold out. hope this helps....or plug it in !!