The problem you just described sounds just like what happen to my vehicle 2 weeks ago when the Injector Module went bad. Originally the Ford service shop told me I needed to get a new fuel pump, then they indicated a new fuel pump pressure value, then they said I needed 4 new injectors and a new wiring harness. ($3,200.00) I had the vehicle towed to another highly recomended service facility to get a second opinion. Within one hour they diagnosed the problem as the injector module. The present injector module is just 2 months old, so I had it towed back to the Ford Service facility and the warranty injector module installed. My van in now running perfectly again. The are telling me as the 7.3L engine ages the wiring harness becomes brittle and there for can send inconsistent volts of electricity through the system as the vehicle travels down the road. This over time will mess up the computer inside the injector module. If your having problems with injector module at high mileage (288,000 me) perhaps the wiring harness needs to be replaced.

 

Im not sure Im gonna start it up either tommorrow or Sat and unplug the harness to see if there is any change. And maybe try to check for injector voltage if I can get a pinout.
I'm actually leaning toward suspecting the IDM since this would be the 3rd one.

 

Wow I never thought of the harness.
I do have 250,000 miles on it.
I would have 3 bad IDM's in 3 years if this one is bad.
Did you actually have your harness changed?
How big a job is it to change the harness?
Are you talking the entire underhood harness?

I would like to eliminate the real problem if this is it.

 

I have not as of yet changed the wiring harness. I as you, would like to fix the problem at the core. I am in the process of getting a quotes. Bill Currie Ford in Tampa Florida has quoted two injector harnesses, one at $493.86, and the other at $187.75. I understand it is somewhat of a time consuming job. They also quoted 9 hours to install at $80.00 @ hour which brings the final total to $1526.47. I am not much of a motor head. This vehicle has been such a work horse for me that I want to keep it going. When I average my total repairs over 8 years, add in my total aquistion price, I have been able to operate this vehicle at a very reasonable monthly cost. Specially when you compare it to something new.

 

Hmm changint the harness at $200 wouldnt be bad.
Is the harness ONLY between the injectors and the IDM?
What about the glow plugs in the UVC wiring?
Do they go back to the IDM?

 

wow guys please dont pay to have that done. its a very easy fix. the 400 dollar price sounds more like it for the harness.


btw if your harness is bad it will be the 2nd one i have heard of in all my time of reading here and another place. best of luck.

 

The bad harness you heard about was it tore up real bad?
Or did it look ok but turned out bad?

 

neither. the wires inside were broken.


my .02 your wasting your time with the harness unless your repairing the plugs that plug intothe vc gaskets. but what do i know? i will leave that up to you to decide.

 

Well I'll do a visual inspection on it along with checking the voltage from the injectors.
If it looks good I'll probably leave it alone.