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DrWin
04-15-2022, 01:51 AM
So, I used this handy guide to get the bulkhead connectors correct.
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Which left this little fella out of the action: Do anyone know what it's supposed to be doing/connected to?
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Also, now that I have reconnected to two sensors on the Y-pipe and the engine thermosensor on the back of the engine to the main engine wiring harness I have three connectors on the same "branch" of the wiring harness that I don't know where are supposed to go. I think the two on the left were disconnected when I took everything apart, but I'm unsure if that is the way things are supposed to be or just the way things were on my car. (I've found many special decisions implemented.) Anyone. What are these and what, if anything should I connect them to?
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cis6409
04-15-2022, 10:30 AM
The 3 connectors,
The ring terminal with the red heat shrink looks like the ground for the fuel ecu.. Its bolted to the the back right of the intake manifold usually beside cylinder 1.

The small connector on the left looks like the connector for the vac advance solenoid

The middle one looks like the connector to the reversing light switch but can't tell for sure as the dirt is obscuring a bit

The red female multiplug should have its male counterpart in with the rest of the main bulkhead connectors beside the coil. On a manual only a couple of pins are used in that plug for the reverse light circuit but still needs to be connected.

Michael
04-15-2022, 12:41 PM
It's a great time to take those three brown wires that run from the bulkhead all around the engine to the alternator and completely remove them from the harness. Get a 4 gauge jumper and run it from the unused hot point in the coil box to the alternator with proper fittings. It shortens that run by more than half and my give you a stronger reading on your volt gauge.

You can then tuck the remaining part of the harness under the intake runner for a clean look.
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DrWin
04-17-2022, 01:23 PM
The 3 connectors,
The ring terminal with the red heat shrink looks like the ground for the fuel ecu.. Its bolted to the the back right of the intake manifold usually beside cylinder 1.

The small connector on the left looks like the connector for the vac advance solenoid

The middle one looks like the connector to the reversing light switch but can't tell for sure as the dirt is obscuring a bit

The red female multiplug should have its male counterpart in with the rest of the main bulkhead connectors beside the coil. On a manual only a couple of pins are used in that plug for the reverse light circuit but still needs to be connected.
Got it - so this is where the ground goes?
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It's a great time to take those three brown wires that run from the bulkhead all around the engine to the alternator and completely remove them from the harness. Get a 4 gauge jumper and run it from the unused hot point in the coil box to the alternator with proper fittings. It shortens that run by more than half and my give you a stronger reading on your volt gauge.

You can then tuck the remaining part of the harness under the intake runner for a clean look.
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Nice - that sounds like a great way of tidying up the harness a little. :)

Bonus question: I have a single black wire coming from the firewall near the ballast resistor and a bundle of 6 black wires coming from the main engine wiring harness, that I think belongs on the drivers side of the intake manifold, but I'm not entirely sure. I forgot to take pictures of this part while disassembling the engine. Is this the correct location for these grounds?
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Michael
04-17-2022, 01:26 PM
Got it - so this is where the ground goes? 68371


Nice - that sounds like a great way of tidying up the harness a little. :)

Bonus question: I have a single black wire coming from the firewall near the ballast resistor and a bundle of 6 black wires coming from the main engine wiring harness, that I think belongs on the drivers side of the intake manifold, but I'm not entirely sure. I forgot to take pictures of this part while disassembling the engine.
Is this the correct location for these grounds?
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Yes. I don't know how many wires attach there and that number may be different depending on drivelines, but that is a ground attachment for several wires. Would not be a bad idea to sandpaper all the mating surfaces either. PS, that's an old pic of my engine bay. I have since added different intake and throttle covers but that one shows the tucked harness better.

DrWin
05-05-2022, 01:09 AM
Yes. I don't know how many wires attach there and that number may be different depending on drivelines, but that is a ground attachment for several wires. Would not be a bad idea to sandpaper all the mating surfaces either. PS, that's an old pic of my engine bay. I have since added different intake and throttle covers but that one shows the tucked harness better.

Again, thanks for the help. And the picture. I like to get some inspiration for my own car, so I'll have to live with the engine bay envy I get from seeing yours. That looks really good! I was hoping to clean up my own engine bay this winter, but I didn't get very far. Some day...