Hey guys, i have a 2002 f250 7.3 powertroke with 120,000 miles, my problem is it will not start unless plugged in, even when its hot out side, it will only start if my engine oil temp is above 100 degrees, i have had problems with hard start before and its always been the GPR, well i replaced it with a new one and it made no difference, I have new glow plugs but have not replaced them yet 'cause not convinced that is the problem, could it be the injectors, it runs great when it starts not rough or anything at all so not sure about that, i have had to use either a couple of times to start it when i forgot to plug it in ( I know, not good, and i cringed when i had to use it but i had to get home from work) but even then it fired right up and ran great, i had an oil leak in one of the Hpop lines o-ring replaced those 3 but still no change, does anyone have any ideas as to what might be the problem or what i should check, should i go ahead and change the glow plugs, i put new ones in about 3 years ago