I suspected I had a bad IP, after replacing 2 known good PDM's, new crank sensor ,good lifter pump. So now that I've replaced the new injector pump with a new pdm to. I still can't get fuel to the injector lines. I've checked the fuel shut off the plunger def comes up. But one thing I noticed is my glow plug light doesn't come on. Should I suspect bad ecm or glow plug relay controller? Can this shut down my injector pump? I know the yellow wire going to the relay is from the ecm I have no power coming from it only a constant at the red. I've unplugged the optical sensor and turned it over still no fuel as the same with crank sensor. I've spent a whole weekend beating my head on the steering wheel and pulling my hair. I've come down to those conclusions either a bad ecm or relay control module.

 

I also for got to mention its a 1994 6.5 turbo blazer

 

Hi have you cracked injectors open and turned engine over to bleed you have air locked the fuel system
Make sure ignitions on so injector pumps open
Best way to do this is get an oil pump that you sick oil out off engine
Connect it to the injector pumps fuel return pipe get some hoses on your oil pump tube to fit tightly on injector pump return pipe
Them pump oil pump up to create vacuum on return pipe and it will draw the fuel and air out off pump with ignition on but not starting it till the airs cleared in fuel then start it and then tighten 19 mm nuts on injectors. When fuel is pumping out it will start then ok