I realize the code probably wouldn't have anything to do with the starting issue but I do want to get everything I can taken care of with this truck.
This morning I'm going to run up to the ford dealer and buy a new cps and see if that helps the cold start. I guess I'll see if they have the ebp sensor too.

 

While you are there, buy a new tube for it as well.
They rust through pretty easily and start to leak exhaust.

 

I've already checked the tube, it looks like it is brand new.
I ran the truck for a little bit today and when I got home it felt very sluggish....this was new. If I hit the throttle it poured white smoke and smells badly of unburned diesel.
Now I'm a little worried!
I have to do some digging to see what this problem could be.

 

I can't remember if you already check this but how's the fuel pump working? Open the drain and turn the key to the on (not start) and see if you have a steady stream of fuel come out. Just thinking out loud.

On edit. Never mind, you said unburnt fuel. Probably not the pump then.

 

Update:
I replaced the CPS with an aftermarket one. The local ford stealer wouldn't sell me a new gray one (already had a gray one) due to the recall. So I went and bought one at Autozone, just to check it. Installed it and it made no difference. I now have my backup CPS.
I have ordered the glowplugs and they should be here on Tuesday according to OOPS. I'll tear into it when I get them and check each one as I pull it out to see if I have any dead ones. My guess is that I have several even though they ohm test good.
After that I'm baffled and don't know what to do next.

 

I didn't read through all 5 pages but I had something similar happen to me, I had a broken wire from the pcm to the sensors. It was corroded at the firewall and just broke apart.

 

Might have missed this but did you ever have the batteries load tested individually? How about getting the starter checked? You'd be amazed how much faster a new one spins. I'd also guess that it would use less amps too since its more efficient.

 

I have been dealing with some weird starting issues myself the last few weeks so I know what you are going through (although my issues are different and it is below zero here). Did you ever get all your connections cleaned up and check the connection on the starter? I had my starter out today and noticed that the wire from the starter-mounted solenoid to the starter motor was quite corroded and there is only a thin rubber tube to cover it. I took all the wires off the starter solenoid and cleaned all the connections, it seemed to make the starter spin just a tad faster. You might also check along your battery cables for any areas that are thicker than the rest of the cable indicating corrosion in the cable, I had this happen before and replaced a starter and batteries before I finally replaced the cables then got it to start. And a tip here if you do need new cables do yourself a favor and go buy welding wire in 0 or 00 size and build your own instead of buying 4 or 2 they carry in the store.

The things that concern me the most from all your previous posts are the slow spinning while cranking and the single pops you get while cranking. My dads truck the one time would not start even though the batteries tested within range. It turned out they were still good batteries but just weren't spinning the engine fast enough to start it. What are the CA's of the batteries in the truck now?

The single pops while cranking make me agree with your previous thought that you have some faulty glow plugs making only some of your cylinders fire. It could also be a combination of some bad glow plugs and slow cranking. Have you tried holding the accelerator at WOT while cranking? Usually when my truck is trying to fire but not quite starting I will hold the accelerator down and it will then start up.

One last thought. I had an 89 IDI 7.3 that had weak/dead/who knows glow plugs but after replacing battery cables to 00 size I could start it all the way down to 20 degrees with enough cranking and cycling the glow plugs 2-3 times.

So I guess in summary I think your glow plugs are probably a problem but I think your low starting rpm is a bigger problem.

 

This is very good advice.
I've been doing the same thing for customer's cars for 20 years now.
It's one of those things that get's overlooked, but is very important.
Sometimes even doing voltage drop measurements won't reveal the problem unless you are measuring while the starter is in operation and that can get kind of hairy.
I got everything to build this cable from Interstate battery.
It's a VW Rabbit Diesel and the wire size is 0.
00 is as big around as your thumb and would definately be more than just adequite.

 

Subscribing.....
I have had cold starting issues as well. Most cold nights I plug it in and starts right up. But one -5 morning I forgot to plug it in and it started right up. (I have a remote starter) But then some nights at work if I don't drive it all day it will not want to start. I also have to hold the acc pedal to the floor and it will then start up. It will crank, fire then die with the remote starter or if I watch the GPR LED I installed and manual turn the key it will do the same. If I get in, hold the pedal to the floor, it will fire up, rattles, but will start. I only let the RPMs get to a max of 1000rpms then let off the pedal. Let it sit for 5-10 mins to warm up.

 

To answer the question about the batteries, they are 850CA each...I'll have to check to see if that is cold or not, but no matter what I have hooked up (battery jumper box at 200A and good running 7.3L powerstroke with jumper cables) it doesn't spin any faster or make any difference when it's cold, it still won't start.
I guess I don't understand why it would make any difference with the batteries and voltage problems.
I could understand it just fine if I was out of perameters for the truck to start but everything test good and I did replace two cable ends and checked the cables. I also spin the engine plenty fast to start it when cold. Cold here is AZ is not cold though, simply 70* outside doesn't qualify and cold, and it will still not start unless it is plugged in for 4 hours.

It always starts very quickly when the block heater has been plugged in

I'm still putting money on glow plugs. Hopefully I'll figure it out on Tuesday when the new ones get here. I plan on pulling the VC's so it is all ready to put back together once UPS gets here with the new ones.
I will let everyone know how things are going when I get it back together on Tuesday night (if UPS shows up, they have a tendancy to forget my packages all too often).
I will keep everyone up to date as I check further into this fun issue.

 

I guess the point I was trying to make about the battery cables is that the cable from the batteries to the starter or the cable from the starter mounted solenoid to the starter motor can be the weak point in the system. Even though you hooked up jumper cables and a battery charger you most likely hooked them to the existing batteries which still leaves the cable from the batteries to the starter as a untested variable. I just did some searching and found an article that says the minimum rpm for starting a 7.3 is 200 rpm, didn't you mention that your starting rpm was 150?

Here is a quick way you can test the cable going to the starter. Take a good pair of jumper cables and wrap one of the clamps so it will not arc on the block then attach it to the post on your starter, then attach the other end to the positive on one of your batteries. This will give you that much extra conductive capacity to the starter. Now try to start it again. This is how I determined that I had a bad cable on my old truck.

I thought you said it was 40 degrees when you were trying to start your truck. If your truck is still not starting when it is 70 degrees out then that makes me suspect the glow plugs less. I can jump in my truck when it is 70 degrees out and start it right up without letting the glow plugs go through their cycle.

Hope this helps or at least gives you something to think about.

 

That makes more sense about the cable going to the battery. I'll check into that a little more.
The research I've found said 150rpm, but it was still off the forums on the internet and may not be correct. My buddies starts at 150 with no issues.

My biggest issue is that it will start when plugged in and will not start when cold no matter what we do to it. It's totally perplexing.

I'll check into the battery cable tomorrow morning before I teat into the engine to replace/check each individual glow plug.

Thanks for the ideas, I'm open to anything at this point. As long as I'm not throwing money at it.

CrazyKen

 

For those of you just joining the saga I thought I would try to recap the issues and things we've checked so you don't have to read through the entire post to get caught up.

If I plug in the block heater for 4 hours it will start with no issues. Once started it does lack power until it is well within the normal operating temp.

Things we have checked (Barry, a friend of mine, has helped a lot): GPR, it tested fine but I replaced it all the same. PCM powers it up for 2 minutes cold. Harness from glow plug relay to valve cover harness, nothing over .3 ohms and power is getting to all 8 outside pins going to GP's. So looks as if no issues with the GP harness

HPOP level is within 1/2" of top, and pressure is around 600 when cranking, up to 2600 driving (Barry and I went on a test drive when I had it running one day)

130RPMs and batteries test good, with no less than 10.5V while cranking.

Pulled drivers side VC and then #1 GP, turned on the key and got the glow plug to heat up, so I now know that all the wiring is in working order at least to that side. The harness connector under the VC was loose so I thought I had it. I fixed the connector and reinstalled #1 GP and VC. Still no go.

All 8 GPs ohm out good, .5 to 1.1 ohms all the way through to the outside of the VC connector.

Buzz test was performed and all 8 buzzed, although the more I read the more I'm not sure Barry listened to see if any were muted or not. I did hear all 8 of them go both times we did the test.

I even threw in a new CPS a couple days ago with no change.

Tomorrow I'm pulling both VC's off again and every GP out, I'll test each one and see what I get. I have a new set that will be going in if any of them test bad.

Any other ideas or things to do while I have the VC's off will be appreciated!!

CrazyKen

 

The latest new.

Alright, here is the latest.
I pulled the passenger valve cover off, pulled all 4 GP's and bench tested them. cliped the harness back together and turned the key on with all 4 gp's connected...all of them light up. No issue there.

I'm now thinking that I may have a bad injector. The only code we kept getting from the AE was the #8 cylinder (I believe contribution code??) We attributed it to the CPS, which Barry said does happen occasionally.

Any other ideas? I no longer suspect the glow plugs as being bad. They all light up and the harness and system works just fine.