So it's time to install my pricey wire and then also time to take out the excess wire that my mechanic has told me is unnecessary. I'm hoping that someone can educate me on the function of the harness and maybe I can remove even more than I did.
Pricey Alternator Strap:
First, let's add my pricey alternator strap
. As it turns out, it's not super simple although the wire is open for all to see! I couldn't get my 13mm wrench onto the bolt holding the wire to the engine block. I had to loosen the alternator, remove the belt and crank the alternator as far forward as possible to open up space to fit my socket. After figuring out that trick, it was easy to remove the 13mm bolt. The 10mm on the alternator itself was simplicity. Here's the part in place along with the very beat up, but probably still serviceable original grounding strap.
Removing the excess wire harness:
In the picture below, you can see the beginning and end points of the wire harness. The plugs begin near the fuel rail where it tapped into the line to the Air-Flow Meter. It ran under the manifold and had zip ties securing it at the oil dipstick and then near the ATF brake reservoir mount.
Now, at the fusebox, you can get a better idea of how it wires into the relay. There were 3 wires in this harness. A brown ground that is also tied to the ground of the other wire. This ground is interesting as it's weaved around the outside of the insulated wire at the core of the harness. Both these ground goes to one leg of the mystery rectangular relay.
All the other mess of wires had components installed in-line and also wen from another harness coming up from below and then to two other relays. I am not sure what those do, so I left them alone.
I did decide to cut the main harness wire (with the 2 grounds) and did it while my car was running to see if anything happened. So I started up the car then removed the relay. Nothing. So I cut the wires. Once again, nothing. So I pulled out the wire from the plug end of the harness (the plugs will not go through the space threading under the manifold because the plug ends are too big).
So clearly the relay was not needed, at least not at idle; however, I have no idea what all the other wires are for. In this picture below, I labeled the diode that is installed inline. There's another electronic component that I can't make out, but it is sheathed in the same way as the diode. As the car was running (I revved it a few time after idling for 5 minutes) and everything seemed fine. So I just wrapped the cut ends and zip tied the smaller mass of green wires.
So here's the harness out of the car. Now you can clearly see that the ends of the harness was just a tap into the line going to the Air-flow Meter. Also, I tried to make out the part number of that harness. I did a search and found a part number that seems to match, but I can't get a picture of it anywhere or an explanation of what it is for.
This is where the bigger brains of this forum come in. Did I give you enough data or clues to fill in the blanks? Can I remove that mass of green wires and the inline diodes and other components? What do they actually do? I'm all ears.
Meanwhile, I'll report back if I notice anything in the way the car runs. Of course, I can't really go anywhere interesting because of the California "Shelter in Place" order. Maybe a grocery store or an auto parts run if I can think of something else I need.
==< Can I add a 5th picture? >==
I remember a time when this forum would only allow 4 pictures per post. That's why I started creating composite photos. Then, I could have sworn I saw someone place way more photos in one post. So I am going to try and add a 5th. If you see a picture below of my reassembled fusebox with the mystery relay, you'll know it worked. (Nope - looks like I can't add another)
Oh well, how about a link to an externally hosted image then. The mystery relay is the 2nd from right in the photo in the link below.
So why can't we add more than 4 photos to a post? Anyone know?