I just got finished replacing the timing chains and guides on my 2001 F150 5.4 last evening. I thought I had gotten everything back together correctly. Took me weeks to get it done due to not having the time to just work straight through on the project. Long story short, when I turned the key to turn it over I got nothing from the starter. No clicking of a low battery, just accessories shut down and nothing. Being frustrated from just getting 12 hours of work on the project completed I pulled the old jump the solenoid trick and it fired up. When I shut it down after only a couple seconds it sounded like the starter was still spinning. Could I have hooked something back up wrong? I used a Haynes manual to get the process for the work. Disconnected a lot of main wires and took the starter out to get the engine mount bolt out. Any help would be appreciated.
Thanks,
Mike

 

might be the solenoid is shot?? Seems like you could have the wires hooked up wrong?? or wires incorrectly attached at the starter....double check the wiring and where it is suppose to attach

 

I did have the alternator wire on the wrong post but after switching that to the correct one the problem wasn't solved. Replaced the solenoid and still nothing. Turns out that there isn't any power rom the signal wire at the solenoid. Other issues as well but its an electrical thing so I'll move to that category.
Thanks

 

You might've fried stuff when you had it backwards.

 

FIXED! Turns out it was my error on reconnecting one of the large wiring harnesses that bolt together on the firewall. Plugged it in but never tightened the bolt down. Should have made a more detailed to do list.

 

thanks for reporting back....glad it was a easy fix