Mine would start in the morning, put it in gear, start to move then it would shut off and I would get another glow plug light. Start it again, start to move, it would run longer, shut off then GPL on. If I tried to accelerate before it warmed up, it would die. So I would start it and let it warm up for about 5 minutes and it may or may not repeat the shutdown sequence again. After it warmed up, I had no problem the rest of the day. So I lived with that for about 18 months and it happened more in colder weather. Replaced the PITA crank and cam sensors because I was getting the codes. No joy.


Now this startup/shutdown/GPL sequence started happening right after I had Ed FICM repair update my FICM (the FICM update was NOT the problem and Ed does awesome work). There was nothing wrong with it but it was getting old so I did this as a preventative measure. Then it got to the point that it may or may not start anytime and or anywhere. Bought a SGII. With key on I watched the 12VDC and the FICM 47VDC on the SGII. Key on the 12 VDC was good but the FICM 47 VDC would go to 36 then 24 then 10 then 0. Called Ed and sent the FICM back to him. He put my FICM on his shop truck and told me the FICM was good. My X at that time had 121K on it. The WTF, over, light finally went on. The FICM power relay was bad. So I had him do the Ultimate update and got the Atlas 80 tune while he still had it. I replaced the relay and installed the FICM. Fired right up. Never run better. So I took the FICM power relay apart and WOW. The contacts were badly burnt and pitted. Problem solved. My X has never run this good since I've had it. I recommended to Ed that he include a new FICM power relay with all repaired units.


Ed

 

It is amazing how such a relatively inexpensive part can cause so much chaos - though they are needed for the grand scheme of things. FICM Relay corruption / corrosion would be as bad as a chaffed / broken wire.

Good call there!

 

When it does this does it feel like it dropping back to idle?

Here is what I am thinking would be worth looking at.
The EBP sensor is known for shorting at the wires to
plug interface. Take a very close look at the wires and
see if you have some damaged insulation. If this is the
cause of you problem what is happening is one of the
wires has the Vref voltage on it and if that is shorted out
you loose the accelerator circuit.

There is pigtail repair for that connector but first find
the break in the insulation first to prove that is the problem.

If you have a tool for reading live data (good idea) then
look at the Vref. You should see 5 volts.

 

That's a good point Sean, I was thinking EGR if it's still in tack , it rolls with TPS , Throttle position sensor .

 

So the truck hasn't acted up in a week or so. Tonight it did it again. This time I saw two lights, the water in fuel light and the Glowplug light. The lights dimmed for a few seconds, power was lost but the truck did not shut off. It just went down the road for another 45 miles until I got to work.


Any ideas?

 

It actually feels like it is not running at all but lights and radio etc never shut off. It is like a very sudden deceleration.

 

Do you have something other than the SGII for checking for codes?
Check and see if you have any stored codes or pending codes. I think
that you will need something with more abilities then the SGII. If you
find any please post them and we can go from there.