x2. Your problem seems to erratic to be mechanical. And to me, the ignition switch seems most likely.

 

Ok, I'll try to diagnose those this weekend. However the cluster works fine, when cranking the oil pressure, tach, fuel, and volt gauges all respond as normal when cranking on the truck.
I did check all the fuses and they all looked Good so I'll be trying to chase down the ignition and fso this weekend.

 

Hey guys, not meaning to jump in, but I was reading this post and I am having very similar issues, however my truck has not started at all. It was running fine when I parked it, got up the next morning and it would not start. Has not fired or started since. I have replaced and relocated the PMD and the injector pump but still no fuel to injectors. I have checked for fuel and pressure at the T-valve and it is flowing fine. The FSO appears to be working I can hear it clicking. Is the FSO before or after the T-valve? I am also now having an issue with the glow plug relay. The glow plugs were working fine before I replaced the IP. I am now starting to wonder about the switch as well. Do you guys have any other ideas?

 

The FSO on the 94 and newer trucks is on the IP. It's that tall cylindrical thing sticking out of the top of the pump. Very easy to get at.

Perhaps its your ignition switch like the people who have been helping me have mentioned? I am going to try and diagnose that on my truck this weekend. It may also be your ECM. I have read that they can go bad and cause issues like this.

 

I have confirmed that the FSO is operating properly. I removed it from the IP, and turned the key to the ON position, the FSO snapped back as it should. Since I have confirmed this, does wiring a light into the FSO power supply still make sense? I know it's operating with the key, so wouldn't the light stay on with the key as well? Are there other ways to diagnose ignition switches? What about the ECM, are there ways to diagnose that? This is one very frustrating thing about these efi 6.5s is it seems that every problem has the same symptom and it is such a pain to track down.

 

I would still wire in the light,you want to see if the light goes out when you have a stall-that means the switch could be the problem.

The contacts are mounted in plastic and if the switch overheats the contacts move and loose connection till it cools down sometimes,other times they get burnt and the same thing happens.

 

Ok, I will wire in the light.

However, stalling has not been the problem. Once the truck is running, it runs fine. It starts fine all that day, and generally a few days later. Once it sits it no longer wants to start. And currently that is my problem, the truck will not start at all, so that is my main priority is getting the truck fired up again. Currently it is sitting in my driveway in an inconvenient location, and its not eve mobile to get it to my fathers shop where I have the tools and resources to work on it more thoroughly. So currently I am looking for a solution to get the truck started again, and cracking the t-valve or injector has worked in the past, but it not seeming to work anymore.

 

Ok nevermind the light then.

You need to make sure that there is fuel to the IP.

Open the filter bleed and have a friend put the truck in drive and crank the engine.

Close the filter bleed when fuel with no air comes out.

Then crack an injector line loose and try starting normally-might take some cranking,no more than 15 second cranking bursts without a 1 minute starter cooldown.

After a few cranking sessions it should be running if all else is good.

I suspect vacuum in the tank from a bad filler cap or an OPS/LP problem along with an air leak at this point?

 

Just about to go give this a try... One thing, I don't believe the engine will crank if the truck is in drive.

Also, the filter bleeder (the little crank deal on top of the filter housing I'm assuming), will fuel start spilling out once air is bled?

Thank you

---AutoMerged DoublePost---

Ok, I see what you meant about cranking in drive, it operates the pump. Fuel sprayed out with seemingly good pressure. There doesn't seem to be air in it anymore. Cracked an injector, no start after 3 cranking sessions. So I opened the T-valve... No start. I took off the gas cap (which initially made a vacuum noise when unscrewed) still no start, still no fuel at the cracked injector. This is getting really frustrating.

 

don't open the tee valve unless the engine is running.

No fuel at injectors usually means a failed PMD or the IP might have a sheared keyway on the drive gear?