95 E300 Diesel problems after fuel filter change

[EDT]

For the past few weeks I have been having trouble with an occasional loss of power while cruising, but a quick push to full throttle would usually fix it. I chalked this up to partially clogged fuel filters, so today I changed both filters under the hood. I made sure to prefill the filters with diesel and change the o rings on the main filter as well as the prefilter, and to my surprise the car started right up. It stumbled for a bit, but soon settled in to a steady idle and so I figured all the air was out of the system and I drove off.

Just over a quarter mile from my house it lost all power and died so I coasted to the side of the road. It would not restart, only stumble along on the verge of catching, and I quit when it started cranking noticeably slower. After coming back from my house with some tools and extra diesel, I prefilled both filters once again and resumed cranking. After a couple minutes it caught but would only run with me holding full throttle. After another minute or so of it struggling to run, it finally settled into a semi-normal idle and I made it half way home before it died just like the first time.

So now I'm confused and am thinking about everything from leaking fuel line o rings to a fuel pump that isn't working. It feels like it is running off of the fuel I poured into the filter and then dieing when it runs it dry. Why is it not drawing in more fuel and where could air be getting in the system? Thanks for the help.