Considering replacing my harness on my 2000 Excursion with the 7.3. I sent Riff Raff my info and they messaged me back that the harness that was called for on my application was obsolete. Not one to give up so easily, I called Riff Raff and was told that Ford still produces some harnesses for these truck year models with 7.3's, not for the Excursion. Anyone in the know more so than I am if there is a particular harness that will actually work on either a truck or the Excursion? The part # that was listed for my vin was YC3Z12B637BA. What sets these harnesses apart from each other when they are used on the same motor? Mine is not the California model. Has anyone here run into this issue and what was your resolution? Any help is appreciated. Don't want to order a non returnable part that costs $500-$700!

 

Aside from gpr vs gpcm harness, there are a few other differences that can be present based on options and such. I think the biggest difference might be in the pinout in the 42-pin connector. You might, maybe, in theory, be able to get by with repining a harness that is similar enough.
It seems like it would work, but I am just guessing.
Alternatively, you could diy.
I rebuilt my harness years ago partly because the connectors were getting brittle and there was some corrosion in a few spots. I also took the liberty of rerouting the harness to be less in the way, which is nice.
Bought all the connectors, pigtails, and the Ford wedgelock terminals for the 42-pin connector and went through the tedious process of replacing everything. RiffRaff did have the harness for mine but $$$ for made in mexico... diy till I die.

What exactly is wrong with the harness you have? Someone might be able to come up with a better idea for you.

 

All Excursions were California models with a GPCM, except a handful that were made in very Late 1999. Post a picture of your engine bay and so we can see if it is a GPCM or a GPR system. Might be able to help you further.

 

Didn’t realize that the gpcm made it a California model. I just replaced that last year as well as the glow plugs with Motorcraft plugs (hopefully not the counterfeit variety). Yes, I did get them off of eBay from a so called verified seller. The only reason that I was considering changing out my harness was just to do a broad sweep getting rid of the old harness as it’s got to be getting broke down from all the years of oil and heat. Plus, I do have an issue with starting in cooler weather now. I just wanted to start with a clean slate so to speak and not be tearing into the harness as this is my daily driver also.

 

if it starts okay,
leave it alone.

I do NOT believe in fixing what ain't broke, until it is broke.

these folks have the harness

Engine harness vendor



https://swagperformanceparts.com/swa...lifornia-emis/

 

That's not a bad price considering what it includes.

 

Well, I went ahead and installed a new oem cps and now my perdels are all over the place and really running poorly at idle. Any ideas? It was actually running better with the old cps. By the way, this cps was bought from a very reputable dealer that is a sponsor on these forums.

 

I've never liked oem CPS's except the original Black one.

I'd just put the old one back in. Otherwise i don't have any useful input

 

that makes me feel better about snagging an OEM black CPS a while back for the glove box.

 

Yesterday I removed my fuel bowl and install my own version of a 4 line fuel feed to the fuel galleries. Since I have a FASS system I just did a direct feed with no pressure regulation. I used RiffRaff’s flexible fuel lines from my distribution block to the heads. So now, I know that I’ve got a really stable fuel delivery. On the distribution block I also plumbed in a valve to purge air which worked out really well since I made sure that all of the lines coming to the distribution block were inclined towards the block. Also, I checked the resistance from the 42 pin main engine harness to the injectors and all read just slightly above 3 ohms. It’s around 37 degrees here this morning so I went out and started the motor and I still have what sounds like a miss at cold idle. Since my engine is a California version, if I had any issues with the glow plugs, the gpcm should send this info to the pcm and display a code. Right? Is it possible that my glow plugs, or at least a couple of them, aren’t quite performing correctly as in not hot enough. I haven’t looked here yet for the correct resistance value for the glow plugs, but I’m sure that info is somewhere on this site. Any ideas? By the way, I’ve cleaned every connection, checked for abraded wiring harness wires, everything except tearing into the harness which is the last thing I really want to do. Would my recently installed injectors with 30% over nozzles cause this? They are stock injectors besides the nozzles. Bought them from a very respected vendor who is a member on this site. After the engine is warm, it runs really well. Hope my engine isn’t just worn out like me!

 

I have not tested this, but a person could take a truck harness and double check the wiring runs to work for an Excursion. They will require modification.

You will need to install GPCM connectors though being these https://prosourcediesel.com/shop/for.../?gad_source=1

 

The 2002+ harness will be different than 99-01.

Im not aware of different pin outs or different sensors from F-series to Excursion of the same year ranges noted above. In fact, I think you can convert GPR to GPCM and Vice versa by changing the engine harness.

As far as the hard start goes, consider testing your GPR and ohming out your suspicious GP’s first.

 

REF: hard start

temp dropped to 28*F here and I need to use the Excursion.
darn it, I forgot to plug in the block heater the night before.

well, guess I will see how it does on cold oil....
WTS went away, I counted to 60 and started it up.

it loped real bad for a few minutes,
lucky I only needed to drive around behind the shop and test the RV hookup wiring, are all the lights working?
" yes they are "
put the truck back in the parking spot,
and it had smoothed right out by this time.

over 175k miles and stock engine... it don't like 15w40 T4 in frigid weather

 

No diesel does. 5w30/40 would be mucho better during the cold months. would eliminate a lot of issues; especially in the work truck world.

 

5w40 synthetic Rotella in cold months is where it is at.