Well it's time to replace the engine wiring harness on my 04 F250, you can only put on so many pigtails and this time it just died on the road and blew fuse 22. So Fairway Ford has shipped one out that should be here tomorrow. I've searched for a step by step for replacing this thing and I can't find one. If there is one on here could someone direct me to it. If not is it possible to give me some tips on what you guys do when you replace one. If some one has a file they could PM me that would be awesome. The one I was sent back when I did the HPOP was extremely valuable and made the job so much easier. Can't thank you guys enough. Let me know. Thanks in advance.

 

I'm sure the information exists somewhere in the ford tech files, but I've never seen it posted here. It's not that difficult, for the most part, but it is rather tedious and a little labor intensive. Take LOTS of pictures and remember it's just like putting together a big puzzle. Maybe Yahiko (Sean) or TooManyToys. has that stuff.

 

I don't. I took pictures of how it laid out, but that was for my generation of the harness. And now I have some modifications.

Lots of pictures is the best idea.

 

Would you share your photos?

 

Does your 04 have the 03 engine?

 

Here is a thread that may help a little

https://www.ford-trucks.com/forums/1...e-harness.html

 

I'm curious on this too.. I have a 2004.5. Don't have any problems, but I to would like to see some pics of the process.
Bismic is there a big difference in 2003 and 2004?

 

Got my answer on that link. Thanks😞

 

There a few different harness and therefore layout. Here is a dump of most of the stills, but I have videos where I narrated details which were more important to me.

 

Here is a youtube video that might also help (but it is an 05 in this video):

 

I started a post in 2019 ( not sure how to link it here) on where the harness should run coming around the fuel housing.
Genius mechanic I had do work put it under mounting plate and when I asked said that's how he has done for years and that's how Ford does it. Y'all put out some good info on how the harness should be run.
The pics up top are great. Good baseline.

 

Take lots of pictures like Jack said, watch for chafe spots on the old harness and either re-route or protect the new harness. The hardest part on my 03 was the crank sensor, pretty sure I had to loosen the a/c compressor.

 

That was the worst spot on my 04 also, probably on all of them. I know that going with the 05-07 injector harness made a little more room up top too, but that may not work on his truck if it's the 03 motor.

 

Good add, Mark. Like I said......a little labor intensive but Mike Chan gives good advice.

 

My images and videos of this were not composed for public use, it was just to get me back together.

Anyway, I said I had video work so I dropped them together if there is something there will help. I also added where I used a borescope to hunt around the intake for anything that should not drop into the intake ports before lifting the manifold. You can wash, you can use compressed air, but there is always a chance something gets bounced around so I feel it a good idea to inspect. At this point, the intent was to pull only the driver's head and backplate to change one lifter in this Pandora's box. So anything down the hole on the pass side was a concern.

That covers about four minutes in. I've tacked on some of the work I did in prepping and recovering the two harnesses. I actually made a video that ran about 45 minutes about recovering the harnesses, it was the most damn boring video one could imagine. But it shows the process and the tape I used, along with other tapes. Ford specs the shiny surface tapes for the engine compartment, the fleece surface tapes for the interior. It's my contention they believe the fleece tapes retain moisture from dew and rain, which can enhance the possibility of shorting. I stayed with the original materials the outer covering and used a little of the Elliot 935 tape as a cushion underneath. The rest of the unpublished video shows the tape work.

The 277 tape rated for 257ºF was the tape I used, shown at 9:10.