GREAT BIT OF INFO, MUST READ!!!!
i work at a shop that specializes in commercial fleet vehicles. we recently had a 98 E350 powerstroke come in that had a weird problem. it would randomly loose power, start missing and eventually shut off completly. we pulled out hair out to find anything because we could not get it to act up. two days and 500 miles after the customer came and got the van it quit again and had to be towed to our shop. this time we had no choice but to drive the thing untill it acted up so we could get a better idea of what happens when it dies. i drove that van 100 miles untill it finnally started missing and bucking. after a scan, it had no codes, it buzzed fine and also had good contribution on all injectors. being that this is one of our larger clients we elected to pull all 8 injectors and have them tested. 4 came back bad from arundel fuel injection. the customer said to replace all 8 since the truck has over 200k miles on it and he planned to run it for a while longer. easy fix right, wrong. three days after and 600 miles later, again it dies and has to be towed. i started to check other things that might cause such a problem like fuel pressure. i found that the truck only had 10psi of fuel pressure from the electric pump. i pinched the return line and i had 60 psi. after checking i found the regulator on the fuel can to be bad. the o-ring had broke and was holding the regulator open. again, easy fix. i now had 60 psi of fuel pressure. the van sounded much stronger and had alot more power. i drove the van no more that two miles when it started bucking and loosing power. it seemed like it was out of fuel. i hooked up my fuel pressure gauge again and was still seeing 60 psi of pressure. i came home that night and was on the net trying to find any answer or possible thing to check to help me. i was running out of things to check. that is when i came across a thread that had the same problem listed in the title. it said that after replacing much of the same things i had replaced, he was told that there was a fuel filter in the tank. after he had checked, the guy was right. there are two small plastic screens in the tank sending unit that clogged on his truck. fixed his problem. i got to work, drove the van with a pressure gauge hooked up and saw that the reading would drop when hard on the gas to 0 psi. big problem. i pulled the tank and found the screens completly clogged, and the inner liner of the tank was coming apart and putting little paint shavings all over the place. after cleaning the tank and cleaning the screens the van had 60 psi at all times when driving and the van was fixed. i just thought i would spread the word. i have worked on these motors since they were put in fords in 94 and i had never heard about any kind of filter in the tank. i hope that this helps someone who is chasing a problem. my advice, any running issues, put a gauge on and drive it for a while. any pressure under 40 is not good and could cause detonation according to my information system at the shop(alldata). the power difference with the higher pressure is big!!!!