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While trouble shooting the many problems of my 89 Graduate, I found this:
What is the best way to repair it? I am concerned about the braided shielding. What would be the problem if the shielding is not connected properly to the flywheel sensor harness?
 

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While trouble shooting the many problems of my 89 Graduate, I found this:
What is the best way to repair it? I am concerned about the braided shielding. What would be the problem if the shielding is not connected properly to the flywheel sensor harness?
That's a pretty ugly sight. The purpose of the shielding is to keep external interference, such as noise from other electrical wires, etc., away from the signal that is carried by the flywheel sensor wires. It may not really be necessary in our application, as we don't really know what environment the Bosch engineers had in mind when they designed the L-Jet system. (Recall that many makes of cars used this system, so it was probably over-designed to be usable in different applications). The shielding is connected to ground, so you probably can't just not connect it, but I doubt that the shielding needs to be perfectly intact.

As the photo shows, the stray bare copper strands appear to be making a connection between the ground pin of the connector and the braided shielding. So while not looking very professional, it is probably accomplishing the goal of providing shielding (where the braided shielding is still in place).

I would be more concerned with the missing insulation on the two signal lines (tan and white). At a minimum, you should wrap each of those bare spots on the signal lines with electrical tape. (don't wrap them together -- wrap each one separately). Better still would be to carefully remove each pin from the connector (there should be a movable plastic tang that engages a corresponding tang on one side of the metal pin) and slide some shrink wrap insulation onto each wire, and then shrink in place. If you take all of the pins out, you could then install a larger piece of shrink wrap over the entire harness (after shrink wrapping the individual signal wires), and then reinstall the pins in the connector.

When my signal wires got to the same condition as yours, I purchased a new Bosch 3-pin connector, and splice-connected the two signal wires to the corresponding wires on the pigtail from the new connector and then connected the braided shielding to the ground pin (at least in concept as it appears in your photo).
 

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What would be the problem if the shielding is not connected properly to the flywheel sensor harness?
The shield (aka drain) wire is to prevent weak/sensitive signals from being affected by ElectroMagnetic Interference (EMI) that may be emitted by other nearby electrical devices. An altered flywheel sensor signal may result in an ignition misfire to perhaps engine shutdown (unlikely though).
Drain wires are typically connected electrically only at the device on the receiving end of the signal (the ECU in this case) and not at the transmitter. The sensor harness however is designed to be shielded hence the 3 wire connector for the 2 wire sensor.
I've repaired countless shields in both automotive and industrial applications using the method in the link provided by Eric.
 

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Discussion Starter #5
A big thank you to all who replied. You have given me great information. As always, this forum rocks.
 
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