Wire wrapped in foil?

I was searching the wiring harness for shorts, when I noticed a wire that seems to be wrapped in foil. It starts over on the passenger side wheel well, goes over the A/C Compressor and branches off at the Cam sensor/ crank sensor break.

The wire that goes to the cam sensor only goes about 1/4 of the way to the connector and then suddenly stops.

If you pull the shielding back, it's just a bare wire?

Anybody have any idea what this is for?

It's called a case ground by Ford. The foil is to shield the wire from external sources of EMI. It works!!

While most here will either have no knowledge or not recall the GM products of the early and mid '80s had terrible problems with EMI from external sources simply because they didn't feel it important to provide so many grounds to low voltage PCM inputs/outputs.

deepbluesc said:

It's called a case ground by Ford. The foil is to shield the wire from external sources of EMI. It works!!

While most here will either have no knowledge or not recall the GM products of the early and mid '80s had terrible problems with EMI from external sources simply because they didn't feel it important to provide so many grounds to low voltage PCM inputs/outputs.

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I appreciate an answer so quickly.

My question is now why does it branch to the Cam sensor but doesn't go all the way to it? Stops about 3 inches short. You would think it would continue all the way, right?

Nope! Actually it covers a number of primary ignition wires/signals in the area(s) that Ford considered to be of high EMI potential. It wasn't necessary to go from one end of each to the other just the places where they were worried interference could be an issue.

deepbluesc said:

Nope! Actually it covers a number of primary ignition wires/signals in the area(s) that Ford considered to be of high EMI potential. It wasn't necessary to go from one end of each to the other just the places where they were worried interference could be an issue.

Click to expand...

I feel like a complete idiot now, but thanks for the info.

****, and I thought maybe it could be that simple.