I have a 96 F-250 7.3 WITH 200K on it, i bought it last March  with 180K and have replaced the Transmission, batteries, alt, starter, fuel pump and Glow plug relay's,

2 months ago after the truck started to stall while driving and would take a few minutes to start back up, and seemed to have no compression while starting…. I took it into a shop that specialized in F series trucks in my area, they have since replaced the Injection drive mod, Injection pressure regulator and controller, the injection wiring harness and 1 injector, when it was all back together the truck was said to run great at times that all 8 injectors are firing and then will have times when it will cut out and misfire, injector balance test show no faults, they found a slight amount of rust on the fuel portion of the injector, this injector was replaced and everything was put back together, issue with cutting out or miss-firing still exists, thought now is the injectors could have bad plungers (rusty) and it was suggested to replace the injectors as needed upon inspection of each,

My thought is if the plungers were rusty wouldn't that allow for more fuel to fill the cylinder and create more smoke and HP?

I put this out here to see what everyone thinks of this situation and my major concern is if all the injectors were replaced and issue is still present where does one give up?

Is this a valid thought that it will cut out due to rusty plungers? To me it sounds like it could still be electrical?

Any insight would be great, the truck is super clean and a very straight body, I would like to fix it but unsure if the diagnosis is going in the right direction of if I could just be squandering my hard earned $$

They also say that the fuel heater is missing from the truck (under the valve cover) but I have plugged it in overnight during the winter and it allows it to start right up in the morning, I do have the issues to a similar post where if I’m at work all day and don’t have the means to plug it in it will be VERY hard to start, I did replace the Glow Plug relay but it still seems very hard, almost 20-30 minutes, turning the key forward and back 10-15 times seems to get it going, my thought is the factory fuel heater was removed and some other type of heater was installed which the repair shop missed, is there a proven technique for cold starts, and this was 40 Degree type weather!!

Any Help would be greatly appreciated as the repairs above are already at 3k!! And I could be looking at another 2.5K to finish the injectors……..

Thanks in advance for and help  

i would find a donor truck in a junk yard to get parts off of there should be some in your area just cuase its in a junk yard dont mean it junk cuase your not sure whats worng with it now