Smoking when cold
2003 6.0 studded and deleted. On cold starts truck smokes pretty good until warmed up. No problems starting truck and truck doesn't run rough at cold start. The truck has not thrown any codes, the fact that the truck is not romping or surging when cold leads me to believe it could be the Glow Plug Module? How do I test the glow plug module?
Truck just started doing this recently, I could swear when I used to wait to start I could hear a definitive whine from my glow plug module and the whine is not so definitive now.
Am I heading down the wrong trail?