Alrighty here, so just kinda explaining my situation real quick. Just moved to Washington from Texas for better opportunities, anyways there is an '89 F150, 351, 4x4 that I just got to put my hands on! Very well could be my next ford for me. If I can talk the owner out of it

So the back story for this truck the engine has been taken out, had some head work, cam, and other stuff I cant quite remember. Im not sure if this problem was there before the work but the problem im having now is that when I go turn the key into the on position, the fuel pump runs constantly and cause the truck not to start. What I had did today, well I did some research and the only thing I checked was the fuel pump relay, unplugged it and turned the key on and the fuel pump didn't make a single sound. So I plugged the relay back in turned the key and the fuel pump once again would run constantly.

Some backyard work has been done to it so idk if its a common ford problem or someone messed up somewhere. Im talking to the owner he just told me that it runs sometimes and then just shuts off and wont start for like a week. He replaced the computer and the fuel pump, and its been having the same problem I described. He also said that he would take the battery out for a week or so, would put the battery back in and would start right up.

The owners theory is this: The windshield used to be cracked and possibly leaked water into the cab, he thinks there could be like a bad ground behind the dash, but I really dont know what the problem could be.

Any help is very appreciated!!

 

I'm pretty sure your in the wrong forum..

try here,
https://www.ford-trucks.com/forums/forum28/

and is that a 351M or a 351W?
I'm fairly certain its a 351W so try here,
https://www.ford-trucks.com/forums/forum55/