I recently went offroadin on a trail Ive been taking for four years now and never had any issues untill this time. When I crossed the river I pulled up out of the way to watch some friends cross left the truck running and when I came back my truck had shut it self off. The Fuel pump wasnt working I checked the fuse, and I checked the fuel pump shut off they were fine so I ended up letting it sit for a couple hours and it started up and made it back through the water hole and out of the trail like nothing happened and still to this day it works fine. does anybody know what I should be trying to waterproof considering Im planning on taking this trail again. I have a 2006 5.4L xlt

 

Might be worth a try to check the Fuel Pump Driver Module.

It is water resistant, but I would not consider it submersible.
Don't know if making it water tight is a good idea ( condensation cannot get out, causing damage ).

Thread from the Technical Articles section
https://www.f150online.com/forums/ar...placement.html

 

thanks Im going to take a look at it tonight what do you think if i was to spray it down with some sort of moisture repellent like a silicone spray or a undercoating spray.

 

Undercoating could seal it shut, water displacer might help, but that would only be for a short time.

The module was not designed around be 100% sealed, when you look at how the 2 covers come together.



Those are just plastic clips holding it together.

That is if this is what is causing the issue, could be something else.

Might want to check the other connectors back there if you are getting them underwater.