I have a 1988 F150 with a 5.0 liter engine and dual fuel tanks. The rear tank rusted through and I replaced it along with the internal fuel pump/sending unit. I had alternated my tanks prior to this and ran several weeks on the front without incident. I ran about 100 miles on the new rear tank before switching back to the front. This is when my troubles began. I drove about 1/2 mile when I noticed a hum that got increasingly louder until the engine died. I switched back to the rear and the truck started. I drove a couple of miles switching again to the front only to have the same experience as before. I have since replaced the dual function resevoir, the internal pump on the front tank, twice, and the tank selector switch, all to no avail. The duel lines have been blown out; I read 13.67 volts at the harness connector to the tank while using the harness ground. The pump discharge pressure is almost 8 lbs. I have switched the fuel lined at the resevoir to rule it out. Despite all this, when I attempt to run the front tank, the high pressure pump starts to whine after a couple of minutes, as if starved for fuel before the engine dies. It dies sooner when being driven, but will idle for a longer period of time before it dies. What have I overlooked?

 

[updated:LAST EDITED ON 28-Mar-02 AT 05:29 PM (EST)]have you checked to make sure your fuel filter isn't clocged?

there is problably something stuck in the line of that one fuel tank wich hasn't been blown out yet