88 F150 4.9 Litre Straight Six Fuel Problem

[Mark Gibson]

Greetings...Hope this finds you all well. Need some advice on an 88 F150 4.9 Litre Straight Six motor. Its a a truck I use for hunting only. The motor developed a problem with it appearing to be starving for fuel. It will idle, but when you let the clutch in and start off, it will stall, and will not refire, unless I spray some either in the throttle body......it will run off of the either just fine, but as soon as it burnes it off, it starves for fule again. This truck has 160,000 miles on it, and I do not drive it a lot at all.
It has dual tanks, and looking in the driver side frrame rail, I see a mechanical Dual function reservior, ahead of it is an external electric fuel pump, and then the fuel filter as you move up the frame rail towards the engine compartment. What I do not know is if there are also low pressure fuel pumps in the fuel tanks, that I should be concerned with. Can you point me in the right direction to determine what I need to replace to fix the fuel issue?

As always, appreciate your suggestions!
Best Regards
Mark G

[idol]

Stalling from take off, and then hard starting afterward. Sound like a very dirty fuel filter which may have partially clogged the TBI. If you brough it to me the frist place I would look is at the filter(s)(dual tanks usually means a filter for each. Also I would either clean or even better (if you can afford it) replace the TB Injector. This would be where I would start if the vehicle came to me...... let me know what you find...IDOL

[Mark Gibson]

Hi Idol.......I finally got to the bottom of the problems. The 19 gallon fuel tank had a bad pump. So I changed pump, tank filter, sending unit, and frame rail fuel filter. Took the high pressure pump out of the frame rail and bench tested it, and it worked fine. Once I got the tank down and the internal fuel pump out, bench tested it, and it was deader then a door nail. Thanks for getting me pointed in the right direction!
MG

[idol]

Glad we could help Mark. Good work. Always keep in mind your troubleshooting procedures and you'll do great. Plus we'll be here to help wherever you need it. IDOL