I went through the diagrams and descriptions in Alldata, and am a bit reluctant to move forward. It turns out that one of the conductors in this plug goes to pin 9 on the 44 pin ECU connector. The other is spliced within a few inches of the engine (within the harness) to the other 2 coil packs, and then goes to the other side of the engine compartment where it is attached to an unfused terminal block directly in front of the fusebox.

The way the sytem works is one side of the coil pack always has 12V, and the ECU grounds the other side when spark is required. Both plugs on the coil pack spark at the same time.

There's no way I'm touching the wiring harness near the engine. I can run one conductor from my new plug over to the terminal block with no problem. From what I've read on this forum, though, it may be very difficult to disassemble the 44 pin connector at the ECU to attach my other conductor to pin 9. My alternative might be to unwrap the wire bundle a couple inches from the connector, and cut the wire (it should be the only black&white one in there), and splice there.

That should work, but it leaves a couple of useless wires in the harness, one of which is tied to 12V, and they are likely to be touching each other somewhere (my original problem, I think). I have to worry about them becoming grounded (if the're not already) and discharging the battery.

Another approach would be to cut away the old plug, slide heat shrink tubing as far down the existing wires as I can, tuck it away and then check to make sure that they are neither shorted, grounded, open, etc. Then maybe connecting my new pigtail to the old wires right next to the coil pack may do the trick.

Which reminds me, the wires on the new plug are tiny compared to the original wires. I'm hoping the originals were designed that way just to make them durable, rather than to handle sufficient current.

Any thoughts on which of these approaches is best are welcome. I'm thinking that I can try the splice at the coil pack approach rather quickly, and if it works I'm done without disturbing the rest of the vehicle. If it doesn't work (which means the wires are screwed up within the harness), then I probably have to try the other approach.

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