Truck Repair: Navistar T444E, ford f350, engine cranks


Question
Hi,
I have a 1996 Ford F350 with the 7.3 Powerstroke motor (Navistar D444E) The engine has 140,000 original miles. I have maintained it well, changing oil every 3500 miles and fuel and air filters as needed. About 10,000 miles ago I replaced the injector o-rings, glow plugs and under-valve cover wiring harnesses. For the past few years (3-4) I had not driven the truck very much at all, probably less than 500 miles a year, it just sat in my driveway, sometimes for several months between starts. In the last 3 months or so, I started driving it again regularly. Everything seemed OK until last week when the engine suddenly started to lose power while driving and running really rough. I barley made it to the side of the road before it died completely. Tried to restart the engine, was barely able to get it running, ran rough then died again. Had to tow the truck home, but once it was in my driveway, it fired up and ran like nothing happened. The next day I changed the engine oil, since the injectors can be temperamental with dirty oil. Fired it up and she ran like a champ... for about a minute, then started to run rough and died again and wouldn't restart. Then I changed the fuel filter and noticed that it was completely black and also found quite a bit of brown slimey stuff at the bottom of the fuel filter housing; it looked like brown snot...nasty. I cleaned out as much as I could, replaced the fuel filter and tried to restart the engine. No go... engine cranks over fine, but won't start. I then changed out the cam position sensor, but that didn't make any difference either.
So, I'm thinking either clogged fuel line, bad high pressure oil pump, or bad injector driver module. Any ideas you might be able to provide would be greatly appreciated. I'm not sure where to go from here. Thanks!

Answer
I Don't work on pickups I work on semis So you might want to check with someone that deals with diesels in pickups. But what it sounds like is as little as you have run it it's grown algae in the tank which has sucked up into your lines. I would go to a napa store and get some algae and water treatment to help get that out of your tank. I don't know if you can do this with a pickup engine but with a big truck engine I've disconnected the lines and blown low pressure air through them to clean them out. Sounds like what you have is plugged the filter with algae and probably plugged the injectors with it too. if your injectors have screens you might be able to blow low pressure air through and get that out of there. But like I said I would probably double check with someone that works on pickup diesels to make sure that's safe.