My 04’, 5.4, 84K miles, F-150 had problems staying running. It would run intermittent, rough idle, and then finally die. It felt like it just wasn’t getting fuel properly. We started troubleshooting, new fuel filter, the fuel module was getting power to it (we couldn’t find a way to check if it was putting power out to the fuel pump), and then finally the fuel pump itself, which would kick on with its whining sound off/on, sometimes I could hear it, other times I couldn’t. No ‘check engine’ lights but it did throw a code for low rail fuel pressure, I think it was P0191. So, we thought we narrowed it down to the fuel pump? Learn from my mistake and you might just save yourself some money.

After we got the new fuel filter installed (don’t ever buy a non-stainless steel filter, if you buy a cheap one they rust/corrosion out and that’s not good), we got the new fuel pump installed (if you buy an aftermarket fuel pump you need to buy the whole assembly, most pumps will not fit into the factory assembly, and if you buy a ford pump its’ a pain trying to place it back in the old assembly, my advice, buy a new assembly if you have to) and the truck still wouldn’t run. We ran a laptop on it, still no fuel pressure?? We checked the fuel module that mounts up by the spare tire, it had power going to it as well? We were baffled?? In all this confusion, throwing tools, cussing, etc. I decided to pull off that module just to take a look at it, I dropped the spare tire down a bit and pulled it off. As I was looking at it, I started messing with it and could hear stuff inside it rattling around, so I started twisting it and it broke in half, it was totally corroded inside. So, we made a late night run to the dealership for a new module. Installed it and the truck fired right up. So, if I could rewind back and figured it was this module, I would have saved myself $300.00. So, end of story, if you have the same problems, install a new Ford fuel filter first, then check that fuel module located at the spare tire (that thing gets beat to death by road debris, rattling from the frame of the truck, and rain, salt, snow, etc. not a good place for it??), then you can move to the fuel pump. If you have to change the fuel pump, look into possibly pulling the truck bed off a bit, I think it would be easier than dropping the tank..

I hope this helps someone out there in the same predicament. Enjoy.

 

Great Post, but there's a few more just like it, except it was figured out before replacing the pump thankfully. I can think of two that were anyway. Maybe if you started a thread before hand, we could of saved you some bucks. That damn module again, -poor design and placement. Maybe Ford has a TSB about that by now, -I'd have to look thru them to see.

Thanks for posting your experience, everyone counts.Glad you got her fixed.

 

He did - it's in the 04-08 forum which is probably why you didn't see it.

https://www.f150online.com/forums/20...tart-help.html

Note post #6......