Mystery wiring

Condor

Low Mileage
Hello all! I have just purchased my first fiat x19. I got a fantastic deal on a 1979 with 50,000 miles on it and no rust. I'm currently in the process of getting fuel to the carb as the cars been sitting in a barn for 20 years. In that process I've found some wiring that looks like it comes through the firewall near the fuel tank and carb cooling fan. (The black wire was tied to the teal one) any idea's on what this led to. The car runs good when I pour gas into the carb and there is a see through inline fuel filter that burps when I try to start the car but doesn't do anything after that. Also just put 5 gallons of fuel into it just to make sure the previous owner didn't overlook that... fuel gauge does not work as well. Could this be for the fuel sending unit? Thanks
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I'm sure there is a wiring diagram for your year model of USA delivered X19, you'll need to look there.

My guess though, is I can see in your picture that the carby blower fan has been removed, my best guess is the wires are left over from the fan motor and its associated relay being removed.

SteveC
 
Welcome! You have some fun ahead of you to make up for the lack of use over those years as well as unraveling the knot of problems the Previous Owner (known as the PO around here) has left you.

To help us help you it would be great if you would put the info about what year X you have and in the future the significant modifications you have made (shaved head, cam, dual carbs etc) as it makes it easier to know what to suggest back to you, thanks for mentioning it is a 79 in your first post.

It is likely the fuel tank will have a bunch of guck in it as others have indicated. One can remove the fuel sender assembly to look inside and be able to use a siphon to get the old fluid out. Some folks have had a ton of thick build up in their tanks and others very little. Removing the sender assembly is quick and easy. There is a plastic cover over the assembly, to remove it is a set of small nuts, be sure to clean them up and lubricate them with PB Blaster or similar to ensure they come off cleanly as some have twisted the stud off the top of the tank which is not a happy repair.

Removing/changing the tank can only be done through the bottom, new ones are available which offer options for use with the standard fuel pump in your car or ports for an electric pump down low. The car has to be lifted fairly high or be on a 4 arm lift to allow access to the area underneath. Some folks have lifted the car as high as they can with their existing jacks and jack stand allow, and then dug a hole under the area the tank come out into.

Until you get the tank drained, I would try getting the engine started using an external container so you don’t add to your problems with the carb.

I would suggest changing the inline filter now (and have a few as back up when they get filled when you do start driving) and consider getting a carb gasket kit as it really should be removed and cleaned given the long time it has been dormant.

Good luck and welcome to the group. Please ask questions as nearly any problem you will run across has been seen and dealt with by someone else here and can help you. Sometimes it does take a bit of back and forth (and bunny trails in the course of the discussion) to get to resolution.
 
The fuel sender wiring is under that rubber cover that you see the 3 fuel hoses coming out of. The 79 had lots of emissions "features" from the factory. Many go missing over the years as people clean up the engine bay. I had a 79 many years ago, but I can only find one overall picture of the engine bay. Here it is:
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Note that the carb cooling fan is out of the car in this picture. So... does your X have that metal cup thingy to the right of the overflow tank? I think it might have have some electrical connections. Post some more pictures of your engine bay when you have time.

Another thought is that Fiat had one harness for the cars, so maybe those are wires for an AC component?

Here is a link to the PDF for the 79 wiring diagrams posted in the Xweb Wiki.
 
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My 79 is unmolested, so I may be able to help here. Did your 79 originally have AC? The green wire is coming from the same location as the AC fast idle electrovalve activation wires on mine. However, there should be two green wires that are twisted together. But this is about the right location. The black wire with the eyelet looks like the ground for the carb cooling fan which has been removed. The AC fast idle electrovalve uses a black ground wire, too, but that should have a connector like your green wire.
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Even if it did not have AC, sometimes the AC relevant wires are part of the wiring harness and hhang out here and there.
 
Thanks for all the help everyone!!
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I moved over the carb cooling fan to take a better photo of the wiring coming out of the firewall. The ground is still connected to the fan. These two wires were separate unfortunately :( I've attached a few extra photos so you can see how the vehicle looks in its current state
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Got the cover pulled back out of the way. The wires leading to the fuel sending unit are tied to the same wire I'm trying to find a home for
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Got the cover pulled back out of the way. The wires leading to the fuel sending unit are tied to the same wire I'm trying to find a home for
The fuel sender wire is green with a yellow stripe. Is that true for the loose green wire? Even where it is in a knot I don't see any yellow. They may be in the same harness, but I don't think that it is the same wire.

Per Larry's post: Since your car is not AC equipped (judging by no AC dash controls), that green wire is most likely for the non-existent AC.

The fuel sender in these cars can rot away if the car has accumulated moisture in the tank. You can see all the small nuts holding the sender top plate into the tank. If you pull it, be careful, the little studs are not strong, so spray them with some PB Blaster or similar rust buster. Also, mark the orientation of the sender top plate so you can put it back the way you found it if necessary.
 
The fuel sender wire is green with a yellow stripe. Is that true for the loose green wire? Even where it is in a knot I don't see any yellow. They may be in the same harness, but I don't think that it is the same wire.

Per Larry's post: Since your car is not AC equipped (judging by no AC dash controls), that green wire is most likely for the non-existent AC.

The fuel sender in these cars can rot away if the car has accumulated moisture in the tank. You can see all the small nuts holding the sender top plate into the tank. If you pull it, be careful, the little studs are not strong, so spray them with some PB Blaster or similar rust buster. Also, mark the orientation of the sender top plate so you can put it back the way you found it if necessary.
Taking the fuel sender off tomorrow. The wire is with the harness but does not have that yellow stripe. I'll start there tomorrow! Thank-you everyone for your replies!
 
Got the car running great yesterday. The fuel lines were hard and cracked. They were sucking a large amount of air instead of fuel. Got those replaced and it purrs nicely. I'm currently trying to figure out what the deal is with the headlight motors. I saw the diode replacement trick and motor testing but I have one set of unconnected wires in the headlight box that looks like it should be connected to the grounding pod in the housing. Any of these colors look familiar? The is in the passenger side (usa) i was unable to figure out what they came from in my book
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I looked at the relays and they seem to be good but the headlight motor relay was replaced sometime before me
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hmmm... spotted something disconnected as well...
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spotted something disconnected as well...
This looks like C40 in the lower right. If you had AC it would lead to the frost valve and the pressure switch.

They made a universal wiring assembly for US cars which could be used for the AC, power antenna and a few other oddments.

A 1979 has a full set of ugly extra electrical features for emission controls.

Have you downloaded a wiring diagram for a 1979 yet?
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1979 wiring diagrams
 

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I looked in my front headlight compartment area, and there are no wires of that color. I am referring to the light blue and lighter blue wires in that first image. Looking at the wiring diagrams for the 79 I can;t even find a two wire arrangement that does a light blue/lighter blue arrangement.
 
I looked in my front headlight compartment area, and there are no wires of that color. I am referring to the light blue and lighter blue wires in that first image. Looking at the wiring diagrams for the 79 I can;t even find a two wire arrangement that does a light blue/lighter blue arrangement.
@Condor I believe that light blue with lighter blue goes to the left horn, the second wire goes across to the right horn.

Odd that they are two different colors of blue.

Page 6 of the wiring diagram.
 
There is no grey either. A mystery.
A big mystery at that. Whoever repainted the car did a good job but oversprayed the wires up front. I'll dissect the horn tomorrow to see if they are the wires im looking at. Currently pulling the pedal box so I can replace the clutch master and brake master.
 
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