The past two days I had problems getting started cold, I waited for the glow plugs and the truck cranked but died right away, and the only way to get it going was to floor the pedal as I was starting. Is this a comon problem when they are cold? Temps were probably in the 20*'s. Both times the block heater was not plugged in, forgot both nights to plug in.

 

Don't wait for the glow plugs, go ahead and crank when the glow plug light goes off.

If you have a fuel heater (it was discontinued at some point) unplug it.

 

Shouldn't be. I never plug in my truck and it starts in the 20s. At least the couple of mornings it has been in the 20s.

 

Check for codes, I doubt your glow plugs are working or your batteries are dying, what is your voltage pre start, with glow plugs on, following startup? You should load test batteries and if they are original, replace with motorcraft 850's.
Also, are you running synthetic oil, 10w30 for winter?

 

I'm running 15W-40

 

Add antigel and cetane boost.

 

Ok, I'll try that, thanks

 

I run 15-40 and have no problems starting in the 20's. I would look at your batteries first. then GP's and GPCM.

 

Basically, that is what Ford spec says it ought to do.

Yes, check electrical system... voltages at different stages..

Key OFF

Key on, glow plug on, pump on

key on gp on pump off

cranking

If he is much below 9.7v on cranking.. there is a problem.

 

While the urge is to blame the glow plug system or even the fuel, most of the time this happens because your batteries are old and need to be replaced.

A new battery that can hold a full charge at 77F loses half of that charge at 5F. Old batteries lose capacity, so when the thermometer drops you suddenly find the 3-5 year old battery is marginal.