Hey brothers I have a 97 f250 with a 7.3. I changed my glow plugs an harness an high pressure pump by the fuel bowl but when the temperature drops to 40 degree an lower it's hard to start I'll turn the key an hear the relay click an when the light goes off I let it stay there a while longer. Once I try to crank it it just turns over an white smoke comes out smelling like fuel. But if I sit there long enuff an keep turning the switch on an off for 5 to 10 mins sometimes it will fire up an smoke but it clears up but you can still smell the fuel. But once it fire up it's good no matter what that day.