Originally Posted by jrcent
2004 6.0 with 230,000 miles on engine. Done nothing to engine except general maint. Now that the air has turned cold the engine is hard to start when engine is cold ( first start in the morning). If engine is cold with warmer air it starts right up. I usually let the pre-heaters stay on for a few seconds when starting in the AM but still no start. Pre-heater light is on before start.This problem just occurred after the air turned cold in the am. ANY IDEAS?
You mean glow plugs, not pre heaters.
Anyways, it sounds like your problem is some where else. You should have no problem starting the truck in 55 degree weather even if the glow plugs werent working at all.