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Mystery wire plugs in 73 challenger engine bay

TeeScott

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All,
Recently purchased a "pretty nice" 73 Ralleye Challenger 340. Car is complete, min. rust, decent interior, and was running and driving when purchased (but did neither well). Have been going through all the usual stuff (brakes, new carb, fuel lines, fuel pump, radiator, hoses, etc...) and am still investigating things like "mystery" wire ends and plugs. Car has had several POs show apparently liked to disconnect stuff/modify wiring.
This pic shows 2 plugs that come off the wiring harness along the pass. side valve cover. Any suggestions as to what they are for" or where they should be connected? I thought the blue wire in the center of the pic might be for the electric choke, but it only carries 1.2V when the ignition is turned or when the engine is running, The green one at the left in the pic is at 0V with the ignition on or off.

THX for any help/suggestions
-TeeScott

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Challenger RTA

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Did or does it have AC? look in the upper right. I'm thinking it's something else. looking for the diagram.
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blubyou340

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All,
Recently purchased a "pretty nice" 73 Ralleye Challenger 340. Car is complete, min. rust, decent interior, and was running and driving when purchased (but did neither well). Have been going through all the usual stuff (brakes, new carb, fuel lines, fuel pump, radiator, hoses, etc...) and am still investigating things like "mystery" wire ends and plugs. Car has had several POs show apparently liked to disconnect stuff/modify wiring.
This pic shows 2 plugs that come off the wiring harness along the pass. side valve cover. Any suggestions as to what they are for" or where they should be connected? I thought the blue wire in the center of the pic might be for the electric choke, but it only carries 1.2V when the ignition is turned or when the engine is running, The green one at the left in the pic is at 0V with the ignition on or off.

THX for any help/suggestions
-TeeScott

View attachment 113081
It looks to me like a alternater wire .on mine one is blue and the other is green and the main batt wire was black
 

Challenger RTA

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It can be difficult to discern what wires are what with out being in hand. As in general the wiring is in generally the same from year to year. With the acceptation of accessories. Or other subtle changes, Electric chock and others. Being the location of termination would dictate the connection, unless the wiring was altered. blubyou340 said: "It looks to me like a alternator wire .on mine one is blue and the other is green and the main batt wire was black."
The obvious should not be over looked. That's to be determined by the observation of the wiring harness and diagram.
 

blubyou340

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It can be difficult to discern what wires are what with out being in hand. As in general the wiring is in generally the same from year to year. With the acceptation of accessories. Or other subtle changes, Electric chock and others. Being the location of termination would dictate the connection, unless the wiring was altered. blubyou340 said: "It looks to me like a alternator wire .on mine one is blue and the other is green and the main batt wire was black."
The obvious should not be over looked. That's to be determined by the observation of the wiring harness and diagram.
Very true sometimes i try to keep things simple for if its a real young kid like my kids. Sometimes fast and easy is what they want to get to that date football game etc. Diagram is always better.
 

TeeScott

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All, THX for the feedback. I do appreciate the wiring diagram and will use it to guide my investigation...
1) WRT the possible alternator wiring: all the "regular" alternator wiring appears to be in-place, the ammeter works and charges the battery as it should. (By "regular wiring" I am simply comparing it to my 1974 360 duster that has nearly identical alternator set-up.)
2) I do believe that one of these is probably for the windshield washer fluid pump that has been removed...(I can check that pretty easily w help from my wife)
3) ALSO...(see new pic) I found this wire that is terminated with a small rubber boot that was laying loose over near the wiper motor. I thought it might be for the installed tach (which isn't currently working), but after running a jumper over to the neg. coil terminal, the tach still is inop. ANY ideas as to what this wire is for?

THX
Tee SCott

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moparleo

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A new engine harness is about $200 if yours is cracked/spliced, missing ends etc...
It also helps to give us a wider/farther away shot to see the whole thing. Just showing a closeup of the wire doesn't give us much context since we are not there.
 

Juan Veldez

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I have a 73 and just went out and looked. My tach wire is gray. I do not see that type of connector on any of my wires within the engine compartment. Follow this wire, where does it originate from? If it gets lost within the wrap, follow the wrapped wires until this color wire pops out.
 

72RoadRunnerGTX

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In the OP, the dark blue wire with the female Packard connector is the power supply to the electric choke control (J2C-18DBL). The green wire with the female Packard connector is the blower motor lead (C5B-14DGN). The female insulated bullet connector is likely the clutch pedal starter safety switch lead (S4-18DGN), 4-speed car?
E-body engine wiring2.jpg
 
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TeeScott

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72RoadRunner/All,
I truly appreciate the support and feedback. I am just now finishing up the install of a new radiator, fuel pump, & power steering pump * will be getting back to wiring investigations soon. Here is some specific fdback:
1) I also was confident that the blue (J2C-18DBL) wire was for the electric choke. But when the voltage with the key "on" was only 1.2V, i figured i was wrong. Maybe the voltage increases once the car is running(I notice that it is tied into the ballast resistor). Either way, I'll follow this wire back through the harness to see if I can find a reason for the low voltage & check it when the car is running.
2) Green wire (C5B-14DGN): It makes sense that it could be for the blower motor. The HVAC system blower does NOT currently work so I'll do some follow-up to check out this possibility.
4) The female insulated bullet connector...the car is a factory auto. Would this 4-spd related connector be installed as part of the "standard" under-hood wiring harness and simply left unconnected/placed inside one of the wiring run plastic sleeves from the factory?

THX
-TeeScott.
 

72RoadRunnerGTX

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.... Would this 4-spd related connector be installed as part of the "standard" under-hood wiring harness and simply left unconnected/placed inside one of the wiring run plastic sleeves from the factory?
No, shouldn’t be there on an automatic, manual only. Another possibility for a female bullet connector is S5A-18BK, black wire, connected to a “Distributor Solenoid” if it had one originally. Would have advanced the timing a bit at start-up, runs over to the starter relay. What is the wire color on your bullet connector? If that's the case, it should show 12v while cranking.

The choke control power should be full 12v in the ignition switch run position, IGN1, same as at the ballast resister, voltage regulator, and one of the field terminals on the alternator.
 

TeeScott

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Roger to all & THX for your assist,
The distributor connection point would make sense as the length and position of this wire along the firewall would reach the distributor just right. (I'l look for a connection point since the distributor is an original style...but I have no idea of its history/originality)
I'll double check the electric choke voltage while the engine is cranking/running.

ALSO, in a previous note, Moparleo stated that a new engine engine wiring harness was about $200... Anyone know of a trusted source for these harnesses, since a full replacement is probably a good idea considering the other splices and confusing connections i am finding?

TeeScott
 

EW1BH27

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What Xcudame said. All my engine bay harnesses are from Bill, no issues. That customizing he can do is a nice feature. I just needed stock ones.
 

halifaxhop

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Those solenoids on the dist fail alot. Most cores I get have them removed. Here is a pic of one. Some are alos one wire if you do not have the solenoid on the carburetor.


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