1978 280z Temp gauge wire to sending sensor

[MessageMan]

After being notified, I’ve reposted this as my last post was unable to be replied to. I’ve tried looking around on Reddit, ZCarForum, and here but cannot find a definitive photo or description of what harness the wire for the temp gauge goes through on a 1978 280z. A few of my harness ends have previously been chopped off - presumably for parts. Comparing to my 75 I was led to believe it would be a yellow wire (per FSM) routed with the other thermostat housing sensors on the FI harness, but could not find it when peeling the wire wrapping back, just the temp sensor and thermotime switch. When I asked on Reddit I was told someone thought theirs was part of the front left harness with the headlight wiring as a green wire, which unfortunately for me is chopped, I saw two green, one going to the distributor and the other being chopped. With the key on I grounded it with a small fuse in line and nothing happened, gauge did not fluctuate and fuse did not blow. Its possible this could be the wire with an open somewhere along the line. For anyone with a complete harness could you trace it back to the main harness and take a photo or point me in the right direction? Thank you.

 

TL;DR 1978 280z where does the temp gauge wire connect into the main harness and what color is it?

[bunkhouse]

Try asking over at classiczcars.com. 

[NewZed]

Might help if you showed a picture of what you're dealing with.  If the engine was in the car and the harness intact it would be in the bundle that runs along the top of the intake manifold.  A yellow wire, according to the wiring diagram in the Service Manual.

 

Here's a web site with pictures.  And what I think is the main bundle that then splits up.  p.s. I don't think it's part of the EFI harness.  The two wire water temperature sensor is but the one wire temperature sender, for the gauge, is not.

 

https://bringatrailer.com/search/?s=1978+280z

 

Edited September 7, 2023 by NewZed

[NewZed]

There's a connector on the way to the gauge.  If whoever cut the harness has been inside the car you might want to check there.  C-1, it's blue.  Also, it might be that in 78 they ran that wire up from the passenger side.  My comment above is about a car like my 76.

 

[NewZed]

1976 is different so my first comment might be off the mark.

 

Here is 1976 -

[MessageMan]

From my knowledge the junction block was entirely untouched, the previous owner had just cut 3 harness points/connectors. The two headlights and the front left harness right next to the horn.

 

Im not currently at the car, otherwise that diagram for sure is something that will be able to narrow down the correct harness! Will update in a day or two when I can get some work done.

 

I’ve attached a photo of where the temp wire was on my 75 (but 78 is lacking entirely)

[Nick280]

@MessageMan did you find it? If so, where was it?