1995 6.5 vin s help

[Chevytruck41]

Hello new to this site a year ago I picked up this truck and it was forgotten about by its owner. Initial problem air in fuel. I.e. Bad fuel lines and hole in tank. Replaced lines from tank to filter housing tank lift pump sending unit and sock. New ops new fuel shutoff solenoid,injectors. Also cleaned two grounds and replaced a third located on passenger side of block. Recently installed a lp relay bypass. This truck will run great for a few days then stall out. Starting up again with no problem. Think it's fixed then bam it will start and die within ten seconds and won't start again. Also replaced the throttle positioning sensor aka pedal assembly. Just about to lose all interest slash nerve in this truck. Worst thing is the truck is solid and frame is also. Have codes and have tried just about everything I know to do looking for a little help here. 210000 miles on truck Ohio is where it has been most of its life batteries new 11/15 harmonic balancer new the list goes on pmd still needs relocated away from first relocation area of the upper intake thinking optical sensor is going but unsure why I have fuel and no air at filter bleeder but will not start or previously start and then die

[a5150nut]

Is it starving for fuel?

Not all fuel socks are diesel

Have you got another known good PMD you can swap in?

[CoyleJR]

It is a long shot but try to loosen the gas cap and drive it to see if the problem is still there. If the tank isn't venting it would run great until it created a vacuum inside and then the fuel would stop flowing. I believe there is a difference between a diesel fuel cap and a gasoline cap.

Good luck
John

[Chevytruck41]

Sock came specific for 6.5 sending unit and it has to be starving after I installed the lp relay it ran great for two weeks then the apps went out replaced ran for a day now won't start period and I bought a brand new diesel tank cap getting codes 22 23 27 31 32 33 34 42 44 45 46 57 62 65 78 84. I realize that most st of these should have gone away with the replacement of the apps. So I cleared them last night still won't start

[Dvldog8793]

Howdy
Crack a few lines and verify that you are getting fuel to the injectors. Given that it had some pretty serious fuel line/tank issues I would make sure all of those are solved. Did you replace the fuel lines with new hard line? Sometimes if you have a leak Pre-LP it will suck air and not be real visible as a leak.
Do a search on this page for "air in fuel"
I assume you can hear the LP running.
What is it doing when you say it wont start? does it turn over fast, are the GPs working? Does it sound like its turning over evenly?
Maybe you have had two separate problems, the stalling and now not starting.

[Wwildman]

Sock came specific for 6.5 sending unit and it has to be starving after I installed the lp relay it ran great for two weeks then the apps went out replaced ran for a day now won't start period and I bought a brand new diesel tank cap getting codes 22 23 27 31 32 33 34 42 44 45 46 57 62 65 78 84. I realize that most st of these should have gone away with the replacement of the apps. So I cleared them last night still won't start

Try disconnecting the computer and clearing the codes and turn key on Do Not Start or Crank . More than likely it is a bad PCM causing a no start or the PDM isBad

[Chevytruck41]

Yes I hear the lift pump running and when I turn on the key the wts is on for about ten to fifteen seconds hear the relay click for glow plugs turns over fast have fuel to bleeder screw but won't start. When I purchased the lp relay it came with a fuel delivery during wts period and a on off switch under the hood for bleeding purposes. Now I notice that I'm unsure if the factory relay is supposed to be used also or left out concerned that it's the ip or pmd again don't want to just throw money at it trying to diagnose will crack injector lines tonight

[Chevytruck41]

Also curious if the pcm is bad do I get one for the s vin or f vin seeing everyone talk about the get delete do I need that pcm or just a chip from a f vin know I need to replace upper and lower intakes and gasket as well all help is appreciated this place is very useful have been working on this truck off and on for a year with small increments of running without problems again thanks to all

[Wwildman]

The PCM does not come with a prom you you can get it from A local part store or rock auto just replaced mine for 83 buck