The main ground for the Glow plugs (10ga wire), and 2 smaller gauge wires for the sensors, and PCM. Is on the rear intake manifold bolt located on the right side of engine. Check for good clean ground, broken wires/connectors.
Problems with this ground can cause all the issues you list.
A bad ignition switch can also cause your issues like a bunch of trouble codes, no start, Ect.

 

I have checked the grounds on the rear of the intake but I will recheck and will look into the ignition switch.
First time in the 20 years that I have owned this truck that it has put me down in the highway. Got to figure it out. Thanks

 

I replaced the ignition switch today and that didn’t help . The SES light came on with one current code which was 0018 cam reference and bunch of history codes I will try to post a picture of that .

 

 

The only time this happens is when I turn the key on and when the glow plug light blinks on for a second and then off I will know the engine will not start ( hot or cold) and when it does start these codes may or may not set . The engine will be very clattery at first like the timing is way advanced .
Now if the glow plug light comes on normally like for 5 or 6 seconds then the engine starts with no hesitation and all is good.

 

That symptom is caused by the PCM loosing 12v. batt. voltage.
Like when the batteries are disconnected.
The ign. sw. is not involved.
Check the fusible links on the buss bar on the firewall.
The batt. voltage to the PCM is one of the small gauge wires/links.

 

Which pin on the ecm would be 12v cause I’m having similar issue

 

Pin C1 on the blue connector, ORANGE wire.
This is for 94-95 obd1 only.

 

I checked all the fusible links at this bar and they all had 12 volts before and after the fusible link.
Today it started normally and I decided to wiggle the wires at this bar and the wires to the IP as well as the main harness while the engine was running and no problem.
i see where it was mentioned to check the 12 v wire at the ECM I will do that next. Thanks for the tips and if y’all have any more they will be appreciated.