One more electrical plug identification

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84_c10_GMC

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ok this should be the last one! I hope lol. I believe the one green is coolant sensor wire but just seems odd location out of the harness. The other I’m not sure what it is. 3 wire plug with a lock clasp around it that holds it on to wherever it goes. Pink blue and light blue wires out of it.

Any and all help is appreciated!
 

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Ricko1966

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I believe that one goes to a second oil pressure switch which controls power to your electric choke,no power to the choke if the engine isnt running
 

84_c10_GMC

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I believe that one goes to a second oil pressure switch which controls power to your electric choke,no power to the choke if the engine isnt running
The 3 wire one? It has a hold down for either the back of the head or bell housing. And wire harness said for oil sensor above filter.
 

84_c10_GMC

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Ricko1966

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No it's not. That's a universal type and I would bet you money it is a normally closed switch for a light. Do all three ports in that socket have an electrical connection or just the 2 opposed from each other?
 

84_c10_GMC

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No it's not. That's a universal type and I would bet you money it is a normally closed switch for a light. Do all three ports in that socket have an electrical connection or just the 2 opposed from each other?
It’s a 3 wire plug. And has a female blade connector on each oriented like that plug.
 

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I looked at my ‘81 because that three wire connector looked familiar- the one that goes to the oil pressure switch to activate the choke when it gets oil pressure . The colors are the same, but mine is a rectangular connector.

The other one very well could be the temp sensor wire. Do you have a gauge? With power on you could tap it to ground and see if it fluctuates.

I went through all of this when I had bought mine with a new engine installed- he had the temp sensor wire hooked up to the electric choke, and vice versa.

Edit- come to think of it, @Ricko1966 helped me through my woes as well.
 

Ricko1966

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It’s a 3 wire plug. And has a female blade connector on each oriented like that plug.
Are you sure there are three contacts I only see 2 in your pic. I think dark blue and light blue share 1 terminal and pink goes to the other,they should be straight across from each other. Make sure the wires will reach to the side of the block by the oil filter,sometimes that switch is in a fitting that splits the port behind the distributor,they will be different sized,so see where your wires reach.
 
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84_c10_GMC

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Are you sure there are three contacts I only see 2 in your pic. I think dark blue and light blue share 1 terminal and pink goes to the other,they should be straight across from each other. Make sure the wires will reach to the side ofvthe block by the oil filter,sometimes that switch is in a fitting that splits the port behind the distributor,they will be different sized,so see where your wires reach.
I will have to look this evening after work to verify if it’s 2 or 3. I know 100% it has 3 slots. 2 vertical 1 horizontal.
 

84_c10_GMC

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I looked at my ‘81 because that three wire connector looked familiar- the one that goes to the oil pressure switch to activate the choke when it gets oil pressure . The colors are the same, but mine is a rectangular connector.

The other one very well could be the temp sensor wire. Do you have a gauge? With power on you could tap it to ground and see if it fluctuates.

I went through all of this when I had bought mine with a new engine installed- he had the temp sensor wire hooked up to the electric choke, and vice versa.

Edit- come to think of it, @Ricko1966 helped me through my woes as well.
I do have a gauge and it’s the only wire left at this point that could go to the temp sensor. I just need figure out how to run it up to the sensor now and not burn it up on the header. Thanks.
 

Ricko1966

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The 3 wire one? It has a hold down for either the back of the head or bell housing. And wire harness said for oil sensor above filter.
(Yes the 3 wire one. ) LOL. I have to admit,I usually just very quickly skim the new posts,and help the ones I can help quick,I rarely read all the text,very rarely open the pics and even more rarely watch the videos. So I saw your post. " "One more electrical connection question",didn't read text,saw your number 4 Pic which showed me what I needed to see,told you what that 1 electrical connection was and moved on. Sorry,you had two more electrical connections. I come back and give more attention when I have time,to the ones that I get alerts on,because obviously the question wasn't answered. Sorry Buddy.
 

ChuckN

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If you haven’t already- it’s not a bad idea to go to Fleabay and pick up a Truck Manual for your year. The wiring diagrams are handy for when you find a stray wire. The wiring diagrams are not the easiest to read (I guess I got spoiled by the Bentley manuals for VW/Audi years ago) but they’re very comprehensive. And of course, you’ll have everything else that it’ll help you with too. Just a suggestion, best of luck to ya.
 

84_c10_GMC

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If you haven’t already- it’s not a bad idea to go to Fleabay and pick up a Truck Manual for your year. The wiring diagrams are handy for when you find a stray wire. The wiring diagrams are not the easiest to read (I guess I got spoiled by the Bentley manuals for VW/Audi years ago) but they’re very comprehensive. And of course, you’ll have everything else that it’ll help you with too. Just a suggestion, best of luck to ya.


I have colored wiring diagrams on the way!
 

84_c10_GMC

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(Yes the 3 wire one. ) LOL. I have to admit,I usually just very quickly skim the new posts,and help the ones I can help quick,I rarely read all the text,very rarely open the pics and even more rarely watch the videos. So I saw your post. " "One more electrical connection question",didn't read text,saw your number 4 Pic which showed me what I needed to see,told you what that 1 electrical connection was and moved on. Sorry,you had two more electrical connections. I come back and give more attention when I have time,to the ones that I get alerts on,because obviously the question wasn't answered. Sorry Buddy.
No worries! I appreciate the help just trying to get this one right while I’m here instead of just making it work.
 

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