I am having a cold starting problem, but I don't think it is glow plug/electrical related. I replaced 4 glow plugs and each of the old ones I took out tested out fine. The glow plug relay is functioning correctly and I tested the glow plug power at the connection directly to the glow plug. The truck will start when it is around 35 degrees but last night it was 17 degrees and it wouldn't start this morning. When it is cold the only way to get it started is to hold the pedal to the floor and crank until it will eventually start. I don't know how the fuel system but I understand that it is fired from the HPOP (haven't checked level, but assume its full because I have gotten it started and it should recirculate to correct level) The truck doesn't seem to be getting fuel... I replaced the fuel filter which was dirty and the fuel in the bowl seemed warm, so I'm also assuming the fuel heater is functioning. I also forgot to add that I put in new batteries and have been running fuel addictives. Can anyone explain how the fuel system works especially in initial starting conditions. One thing I noticed today while trying to start my truck (with no success) was the the GPR was smoking. I have already checked the GPR relay and it seemed to be working correctly and all the connections on it are tight. What could cause this and could it be a reason why my truck isn't starting. Also I used the OBD2 to see if it had any codes and nothing came up. Any other suggestions to try or reasons why it might not be starting

Thanks for any help or suggestions

James

 

...Welcome to Ford Truck Enthusiasts! If you have a minute check out the Guidelines, it will help you to navigate through and understand FTE.
We are pleased you have chosen the best source for Fords!

Enjoy FTE …..
See you on the boards.

 

What you have sounds exactly like what happened to me. I put in a new glow plug relay and all is well although you said you checked it.

 

Under 35 degrees or so ,my 1999 PSD will not start from cold unless the block heater has been plugged in (I guess then it is not really cold). The only way it will start when cold is with ether. The truck has about 65,000 miles on it. I assumed it was the glow plugs starting to wear.