First cold stretch here in Asheville this week and decided to let the truck sit for a few days to see how she did....not too good is the answer. I did new Motocraft GP's and UVCH over the summer to try to mitigate this issue but seem to have missed the mark. I have no codes thru AutoEnginuity and GP's all test fine thru AE; I will Ohm out this weekend.

But given the excursion having a GP Controller vs a relay, anything else I should check while i'm at it?

Do larger injectors have a harder time cold starting?

Thanks All!

 

What are the symptoms? Need some details to help you from the distances we are at.

 

 

How old are your 1.5 sticks?
O-rings?
Have you watched the oil pressure while cranking?
Voltage while cranking? Corrosion in the battery + and ground - cables (and the subsequent voltage drop) can cause starting issues. Are your cables original (15 years old)?
Any oil in fuel filter (black filter element)?
Have your checked the IDM plug for moisture when it won't start? Yes, I know the fender liner is a challenge to remove...
Engine harness connection on top of the drivers side valve cover is clean and tight?
You have gauges?
Fuel pressure while cranking?

Just as an aside to how weird this type of problem can get: have a friend with a '00 X 7.3 that suddenly had a no start one morning. Worked on it for weeks with him (he did work, I gave advice). Ended up being a short in his (fuel/pyro/trans temp/fuel pressure) gauge set (he installed). He installed it on the 12V PCM circuit (it isn't on that circuit anymore!), and the gauges had a short internally somewhere. It was robbing voltage from the PCM through the short, and the truck wouldn't start on the reduced voltage the PCM was seeing. Disconnected the gauges, and the truck started right up first try.

 

Try plugging the truck in for a few start cycles. If it starts up fine each time, you are likely looking at an oil viscosity issue that is affecting the high pressure oil system. Then you are looking at o-rings in the system and solenoids on the injectors.

 

Thanks all...so far the truck has only had any issue cranking in very cold weather, and since it caught me by surprise I didn't have any of my AE hooked up to see IPR readings/etc or my HPOP gauge connected. I'll have that ready next time. All battery wiring is factory (looking for a 7.3 kit now...lemme know if you have a place) but all terminals are clean and well connected.

The sticks are maybe 6mo old...did new o-rings at the time and pressurized the oil rail after to ensure there weren't any leaks and everything was good. I'm using Rotella T6 5w40 and it was changed about 4k miles ago.

 

I got my battery cables from RiffRaff. When I lit it off the first time after changing them, it spun over about twice as fast as it had before. Previous owner was having problems with batteries going dead, and it never really charged right - 13.2-13.5, he went through three alternators and a couple sets of batteries in the last year he owned it. Now it charges at 14.1, they don't drain down, and it turns over like a Datsun on methamphetamine. Coldest I've started it at was 24*, but it was literally no different than starting it at 75* - no glowing it twice, it just spun over and fired. And I still have 15w40 in it from this summer.

I think cables may be the best money I've spent on the old girl. Well, that and replacing the stock airbox that had broken tabs on it.

 

Moved to the 7.3L PSD forum.

Stewart

 

 

It's all good! I know it's habit to post in the "home" forum we're used to.

Stewart

 

At 19F you can let the glow plugs on for up to two minutes also. But it sounds to me to be your controller to the glow plugs. Little pricey but they can be had at salvage yards as well.

 

Update for everyone, everything tested ok...but I think I have it figured out as it has cranked without much issue down to 19* this week.

My fuel pump is not factory, it is a rather robust unit to deal with the WVO, and as such takes a lot more juice to run than the stock unit....I THINK what was happening is that the fuel pump was drawing too many amps and the glow plugs weren't getting full power and under heating.

With the key on, after about 30 seconds the fuel pump stops running, and then I wait another 30-45 seconds and she fires right up without any stumbling.

Just my theory, but it seems to be working for me so far.

 

If you're still looking for new battery cables, custombatterycables.com has a set that is extremely overbuilt but should last longer than the truck. However, they do want a pretty penny for them.

 

I have a CA 7.3 so it has a controller just like yours. When it failed I got no codes or anything. I know your isnt that because it starts, but something for
others.

 

wow...they are expensive.