Can't find my temperature wire - LS Swap

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ih8vols

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Location
TN
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SC
Truck Year
1979
Truck Model
C10
Engine Size
2002 LS1 4.8
I just completed an LS swap on my 79 C10 stepside. Even though I'm only the 2nd owner of the truck, it's obvious the old owner tried various wiring changes because some of the wiring makes zero sense.

The new engine is firing up and running great. The only thing not working yet is my temperature gauge. My new engine has a 3 wire pigtail at the temp sensor coming out of the core - 2 wires that run to the ECU and one (green) that should run to the dash gauge.

The temp sensor worked on the old engine. I just can't find the wire for the gauge. I did not remove any of the old wiring during the swap. All the wires that aren't being used are zip tied under the hood.

Does anyone have a picture of the connector that is plugged into the motor on the original engine? I think that might help me locate the wire.

The only wire that looks like it might be the one I need is in the pictures below. It's dark green and runs into the block head on the driver's side of the truck. This this is it?

Appreciate your help!


https://drive.google.com/open?id=0B0PZQ2m9_AniZXRyNWo1RFZFaXJGVWV1X3Fvbkw5MDI3T1I4

https://drive.google.com/open?id=0B0PZQ2m9_AniLWJzd25jTTV0QXR6RkNVaHpHd3F4YmpWc3JN
 

Charlie

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Don
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1974
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Cheyenne 10 LWB
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350/TH350/AC/4 BBL Quadrajet
:welcome:
 

bucket

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Its normally a spade type of connector that slides onto a round post on the sender. But that is the right color wire. Was the truck a 6cyl?

Does the gauge move if you ground out the wire?
 

75gmck25

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Bruce
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1975
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K25 Camper Special TH350 NP203
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5.7
The wire in your picture does not look like my '75's temp wire or any other wire on my truck. Its similar to the plug on the A/C low pressure switch, but that has two connectors inside.

The temp sending unit wire is green, and has one of two types of connections. My '75 has a button or "nail head" on the end of the temp sending unit like this one. https://www.repairconnector.com/products/GM-Single-Wire-Coolant-Temperature-Sender-Connector.html The wire has a plastic connector with a slot in the end, and it slides on at a right angle to the button. When you slip it on the button this makes the wire point straight up from the sending unit screwed into the head. The last 6-8 inches of the original wire has a black fabric heat protector around the wire to protect it from exhaust manifold heat. Some GM sending units have a standard spade connector on the end instead of the button.

Bruce
 

C10MixMaster

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Kingman AZ
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Ben
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1977
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C10 BIG10
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ZZ4 350
I just completed an LS swap on my 79 C10 stepside. Even though I'm only the 2nd owner of the truck, it's obvious the old owner tried various wiring changes because some of the wiring makes zero sense.

The new engine is firing up and running great. The only thing not working yet is my temperature gauge. My new engine has a 3 wire pigtail at the temp sensor coming out of the core - 2 wires that run to the ECU and one (green) that should run to the dash gauge.

The temp sensor worked on the old engine. I just can't find the wire for the gauge. I did not remove any of the old wiring during the swap. All the wires that aren't being used are zip tied under the hood.

Does anyone have a picture of the connector that is plugged into the motor on the original engine? I think that might help me locate the wire.

The only wire that looks like it might be the one I need is in the pictures below. It's dark green and runs into the block head on the driver's side of the truck. This this is it?

Appreciate your help!


https://drive.google.com/open?id=0B0PZQ2m9_AniZXRyNWo1RFZFaXJGVWV1X3Fvbkw5MDI3T1I4

https://drive.google.com/open?id=0B0PZQ2m9_AniLWJzd25jTTV0QXR6RkNVaHpHd3F4YmpWc3JN


green should be the correct color. the wire end your showing looks like a oil pressure sender connector

You must be registered for see images attach


this is the typical sensor and connector
 

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