ok so i have a 88 ford f250 with a 351w i initially started having hesitation then dying out and now it will run for about a minute and stall then wont run, after a while i will crank it again then will run and die. i have spark even when it doesnt start so i ruled that out. i then grounded the fuel pump relay ground at the under hood port turned key on and i then pressed the valve on the fuel rail and very little fuel came out. i also noticed that the inline fuel pump would make an ugly sound when it wouldnt start so i figured it was going out so i replaced it. still having the same problem i checked the wiring at the switch and at the harness right before the front side tank and i have a good power source and ground. i proceeded to place my ear to the tank and can hear the fuel pump in the tank run and when the key is turned off i hear fuel slosh around. i then figured maybe its the regulator.. so i replaced the regulator and still having the same problem.. i even placed a vacuum pump on regulator to see if it would help with no luck. finally i decided to unplug the fuel line before the filter, turned the key on and had little fuel come out. put that back together and unplugged the line in front of the inline pump, no fuel came out. i put that back together and then unplugged all four lines going into the tank selector thing (i unplugged all four because i was unsure which were the output and return lines) also nothing i repeated to place my ear on the tank and still hear the fuel pump run but nothing comes out. i got the truck after my father passed away and remember he would tell me the rear tank wouldnt work in addition when i removed the fuel lines before the selector brown fuel dripped out of the line for the rear tank, im glad now i didnt attempt to use the rear tank. any help would be greatly appreciated thanks

 

well you have put a very detailed desciption, looks like youve tred it all except that there are screens at the bottom of your fuel pumps, if they are dirty and get clogged they wont pump fuel, get acouple of your buddies together and pull the bed and check it out that way. Its much easier to pull the bed trust me. If the gas in your back tank it brown like you say it may need to be replaced if it does spend the extra bucks and get the bronco tanks and the bigger straps they are worth the money you will go to 35-40 gallons instead of 25-30, i cant rember if the front tank is 15 or 20 i know the back tank is 10 gallons just some friendly advice.

 

thanks that seems like all thats left anything else it could be?

 

hey its no problems MANY times ive had to need help,i guess it could be air intrusion, air getting into the lines some where or even into the tank(s)