Author Topic: Help identify cut wires, missing wires, harness 81 scottsdale  (Read 632 times)

Offline Walnut777

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Still working on some thing on my 1st square body.
Its an 81 Scottsdale 305 auto longbed 2wd.

I have 4 pics here. I cant find a temp sensor connector anywhere.

This pic is just of my temp sensor. I cant find a wire for it anywhere. Not even sure if that's original.

This connector is beside the distributor.  I have no clue what it goes to.

Passenger side on intake I have no clue what goes here

These 2 wires have been cut. They follow back to part of the ac on the firewall best I can tell.
When I was looking at diagrams.  It showed green wire for temp sensor. Maybe I read the wrong one.

Thanks in advance for the help.
« Last Edit: April 14, 2019, 01:22:10 PM by Walnut777 »

Offline hatzie

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Re: Help identify cut wires, missing wires, harness 81 scottsdale
« Reply #1 on: April 14, 2019, 05:03:47 PM »
#1 is an emissions control thermal switch.  The vacuum valve is part of the EFE and delayed vacuum spark advance system.  IIRC the late 70's early 80's GM manual transmission rigs had some kind of thermal switched emissions boondoggle that included the AC throttle kicker and a gear position sensor but maybe this was on the cars only.

#2 is probably the oil pressure sender wire...  Tan? 

#3 is more emissions control hardware.  Look for a part number on it. 

#4 AC LPCO switch, throttle kicker, and compressor clutch are light green.  Can't really tell what color the other wire is.

Temp sender should be dark green and routed along the intake side of the LH valve cover or through split loom with pine tree wire clips along the middle of the valve cover.

#1 & 3 are not showing up in my quick search of the 1979-84 parts illustrations but I didn't spend more than a minute or two on it.  Download a copy of the parts books and take a look in the illustrations...  You actually have the vehicle where you can go look at it and determine if the drawing looks like what you're looking for.  The 1982 & 1983 wiring diagrams may be useful in your search as well.
If you can find a part number on the coolant neck switch and the whazzamadingit mounted above and inboard of the RH valve cover you may be able to put a name on em.
« Last Edit: April 14, 2019, 05:13:42 PM by hatzie »
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Offline Walnut777

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Re: Help identify cut wires, missing wires, harness 81 scottsdale
« Reply #2 on: April 15, 2019, 10:33:01 AM »
I will go below the truck later and see if I see a green wire for temp sensor. The pic with the 2 wires cut are green and lt green.
I don't have an wireloom on left side valve cover.

The one wire plug Im holding in pic 2 is right beside a thing I assumed was a oil pressure sender but it has a harness already plugged into it with 3 wires if I remember correctly.

#4 is dark green and light green.

Offline 75gmck25

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  • 1975 GMC K25 Camper Special, 350/TH350/NP203
Re: Help identify cut wires, missing wires, harness 81 scottsdale
« Reply #3 on: April 17, 2019, 05:24:37 AM »
My truck has two green wires on the driver's side.  One is for the temp sending unit, and the other runs to the A/C compressor.  IIRC, the one for the compressor is lighter color green.  The sending unit wire also has a protective sleeve over the last few inches of wire, since it is so close to the exhaust manifold.

Do you have a temp sending unit in the driver's side head?  This is the stock location for the gauge sending unit.  There may be other temp sending units for emissions devices, but this one is for the gauge.

Some OEM sending units use a post and straight connector, while older ones like mine use a button fitting on the sending unit and a flat wire connector that slips over it.