90 F 150 Fuel pump won't work.

My F-150 was running fine until i shut it off. The fuel pump wouldn't shut off so i unplugged the relay. When i went to start it again, the fuel pump wasn't working. I ran a wire from my battery to the pump and it worked, but the injectors wouldn't work. It is a 300 6 cylinder fuel injected. I thought the fuel pump relay went out, so i replaced it and it still wouldn't work. HELP!!!

I think the relay was the original problem. If you didn't disconnect the battery ground I think you burnt a fuse. Look at the starter the 1989 had fuseable links and I think the 1990 also has fuseable links. A fuseable link is two wire sizes smaller than the wire for the system. I used to keep some extras I would get from the scrap yard. If these aren't burnt check all other fuses.

I would check power from the ignition switch as well, if you contacts are getting loose/shaky, you could be powering up the fuel pump when you shut it off, also, if the truck doesn't know you're turning it on, it won't fire injectors or kick on the pump. I woudl start by checking at the fuses/relays and working backwards until we find voltage. Good luck with it!