I'm stumped on this. When I got to removing the ficm/injector harness the ground wire was wrapped up around the rear valve cover post. I guess the mechanic who did the HPOP drove the nut down and turned the stud in more into the engine winding up the ground wire with it.

The engine has always had 46.5 or 47 volts on the Scangauge and Ford says it read on the low side, too. The truck has a new ficm and it has read the same since going in two years ago. Two new batteries and alternator to boot.

So, I figured the ficm may be grounding out through the brackets and aluminium housing and the ground wire may be damaged in the loom.

Here's a picture showing the loom opened up. The ground wire is bare and has ZERO continuity with all of the ficm pins and injector plugs.

Where does the darn thing go? Anyone know? Thanks a ton.

 

Maybe the bare (inside the loom) wire is only meant to ground against the foil??

 

I've also read that the injector harness does not contain a true ground through the x1 or x2 connectors but the x3 connector that connects to the pcm handles the real grounds. Perhaps the injector harness ground is just for electromagnetic/radio shielding?

Maybe I should just re-wrap the darn thing and get back to putting the F350 back together... What a drag.

 

Looks like it just for shield.

 

The harness ground goes to the stud on the back of the intake manifold

 

That's a great schematic.