I have a 1989 Ford F-150 5.0L 4X4 and i am having trouble with my fuel system. I recently replaced a leaking gas tank (the rear one) I also replaced the pump and hanger asembly at the same time. At first everything was working fine and then 2 days afterwards it died on me while i was driving(it acted like it was running out of gas). It started right back up though after a few seconds of cranking. Then recently it died on me the same way and this time it didn't start back up. There was no gas getting to the motor. After cranking on it for a while i would get a little bit of gas, but not enough to even keep it idling. I towed it home later that day and when i got it home I tried to start it, and it started fine. So i turned it off and on a few time, the first 2 times it worked fine then wouldn't start again. Once again after cranking on it for a while i would get a little gas but not enough to let it idle. Does anyone have any ideas.
Thanks

 

Well since you were tinkering with the gas tank when all of this happened that is where I would start my trobleshooting. First thing to do is check your fuel pressure. You might have a kinked fuel line, a backwards fuel filter, or a bad fuel pump. This is where I would start at at least. Good luck man!

 

Check to see if your fuel pump is running. If it is, replace the fuel filter. A friend who did a tank R&R had this problem.

 

First change the fuel filter on the frame.
If this does not fix it take the hose off going into the fuel tank selector valve from the rear tank with it selected and stick it in a container.
Have someone crank the engine and see if you get gas OK there. If not you still have a problem with the rear tank.
If you do then take the hose off of the frame fuel pump coming from the selector valve and do the same with it.
If OK there you may have a bad pump on the frame.
If not then you may have a bad selector valve on the frame.

Your fuel system:
http://i54.photobucket.com/albums/g9...Fuelsystem.gif

 

I would do exactly what subford said, in the order he said it.

If you're lucky, it's just the fuel filter.

As you see in the graphic posted by subford, there's a fuel pump in each fuel tank, and also an additional high pressure fuel pump between the selector valve assy and the engine.

If the filter is good and the tank pumps work, you could have a bad hi-pressure pump, a bad selector, or a problem with the pressure regulator in front of them.

Good luck!

 

I checked the Fuel pressure today and I am only getting 5psi at the test point (recomended is 35-45psi) i can here the pump when i turn on the key. Could a fuel filter cause it to lose that much perssure. I was also thinking that there was a chance that the fuel pressure regulator could be stuck open and letting the pressure out, becuase after the pressure goes up it quickly drowps back down to 0psi. I am going to go ahead and chance the fuel filter to see if that does anything thanks for the input.

 

Yes the Fuel pressure regulator can do this.

 

Sorry I haven't got back in a while, it turns out that the ignition switch went bad and cause the pumps to work on and off. Everything seems to be working good now thanks for all the help guys.

 

nick, how did you fin out that it was the ignition switch?