Mystery wires and mystery component 190/4

[reidyyz]

I'm slowly going through the wiring and cleaning it up as I remove smog equipment and things get more accessible and I've come across a couple wires that I am unable to locate in the wiring diagram. I have a '76 Spider 1800 that was a Cali car in its' early life and I have the 1974/75/76 WD from Midwest and I can't identify this pair of wires. They are Green and Green/Black, they run up the rh side from the firewall and just terminate about the coil. They look like they were unceremoniously ripped out of the component intended and just left dangling. The smog pump was already out by the time I got the car, so maybe this was the component in question? Can anyone with a smog pump still installed confirm this because I cant even find the smog pump, if it even called that, in the WD?

Secondly and maybe related, maybe not. Same WD (Fuse I and inline fuse, pg 124-6) shows a ground going through component 190/4. This 190/4 is not listed in the comp. list as it only goes up to 190/2.

Any help with these two items is greatly appreciated.

[18Fiatsandcounting]

Henry, here is what I know about your two questions:

1. The green and green/black wires are likely for the ignition mode relay, which is component 128/2 on your M-B wiring diagram. The '76 model had dual points (with slightly different timing), and this relay switched between the two depending on temperature. It sounds like someone may have removed the relay and just wired up the ignition to run on one set of points, which is a very common modification as the dual points were a royal pain.

2. The smog (air) pump system does have one electrovalve, and the EGR system also has one or two electrovalves. Since 190/X seems to deal with the EGR system, 190/4 is probably another sensor, switch, valve, etc. that was part of the EGR system. I've never found out exactly what 190/4 is, so if you do, please let the forum know. Some model years (especially CA cars) also had a catalytic converter "over-temp" warning light, so maybe it's part of that. There was also a switch that was triggered by every time you passed 25,000 miles (25K, 50K, 75K, etc) and it had to be reset to turn off a light. I can't recall what that was for, but it was a reminder to check something related to the emissions control stuff.

-Bryan

[18Fiatsandcounting]

More is coming back to me: There was a mileage indicator that was triggered every 30,000 miles, and it was a reminder to replace the oxygen sensor. Apparently it had to be reset once the sensor was changed in order for the warning light to go off. There is a box/relay under the dash for this, but this doesn't sound like it's one of your issues, though.

There also apparently were warning lights triggered every 25K miles for the EGR system, but I don't know specifics.

-Bryan

[18Fiatsandcounting]

But wait, there's more!! I think 190/4 is a typo, and it should simply be 190/1. Two reasons: 1) There is no 190/3 in the parts list or on the drawings, and 2) the part labeled as 190/4 in one of the drawings has the same ground wiring to it as shown for 190/1 on another wiring diagram (black wire to the washer pump ground and then on to the right front lighting ground).

-Bryan

[reidyyz]

Bryan, your tech support is greatly appreciated. It would have taken me a long time to sort that out without your guidance and once you pointed in the right direction with the 128/2, it all made sense. Secondly, I did indeed notice the disparity with 190/1 and 190/4 from different pages but thought maybe I was missing something. And now I know the diagram may not always be right.

There will be more questions coming only because the wiring in the engine bay is a mess with A LOT of wiring loose/disconnected/terminated from many PO. One step at a time......

[18Fiatsandcounting]

And yet another thought: I believe a '76 California car had a catalytic converter when first sold, while the 49-state versions did not. Catalytic converters also had an overtemp sensor/warning light as part of the electrical system. Perhaps you have all of this, or perhaps only remnants at this point.

-Bryan

[reidyyz]

I haven't crawled under the car yet, but most likely will be a rats nest if the engine bay is any indication. I found the oil pressure transmitter wire disconnected as well as two more (pink,blue), just hanging in the air. Cleaned and reconnected the pr. txter and found the pink and blue wires for the, no longer installed, thermo switch, so I capped and stowed the pink, and completely removed the blue. All in an effort to tidy the engine bay. I even replace three of the relay bases because their clips were snapped, and now they hang neatly back up on the bracket.

Here's some fun facts:
-the fuses are labeled A-I and L because the letters J, K, W, X and Y are not in the Italian alphabet.
- various parts, like tail light assemblies are marked D and S. Destra -right, Sinistra- left. Sinistra- also being 'sinister' like the evil Fred over Flintstone's left shoulder.
-intake filter housing cover marked with I and E for Inverno-winter and Estate- summer. To know which way to install cover to prevent carb icing up.
After all these years, my crap Italian has come in handy.

[18Fiatsandcounting]

After all these years, my crap Italian has come in handy.

Yes, it does help. The markings on the backs of the gauges also correspond to the color(s) of the wire(s) attached to them, which helps. In Italian of course.

At no extra charge, here is today's Italian lesson:

"Guidavalvole per motori a scoppio" means (I think) "Valve guides for internal combustion engines."

Now how cool is that?

-Bryan

[reidyyz]

I'm finding these manufacturer wiring diagrams not so straight forward. I'm used to aircraft diagrams laid out logically. Power source clearly labeled on left, components, grounds and terminators to the middle and right. Each wire in each connector labeled, and a reference with each connector, component and power supply with a location reference.

What messes me is the fact you get power tapped off both ends of a fuse and only one of the diagram shows the battery. Is there anywhere I can find an explanation in the logic of the diagram anywhere? Like maybe Brad Artigue wrote it down somewhere?

[spider2081]

What messes me is the fact you get power tapped off both ends of a fuse and only one of the diagram shows the battery. Is there anywhere I can find an explanation in the logic of the diagram anywhere?

There are a number of circuits in a Spider that are not fused. hence the connections on both side of the fuses. For the most part in the car the top connections are the unfused inputs to the fuse and the bottom connection is the fused output.

I really like Fiat publication titled "Spider 2000 Electrical Diagnostic Manual 1980-1981". It is available for members of the site Mirafiori.com in their library.

Although the manual is not for your car the majority of the information ,circuit descriptions and wire diagrams are similar.

[spider2081]

late 2015 I printed a 1976 Spideer wire diagram from the Mirafiori library. I looked and now I don't see it as available.
This diagram lists 190/1 and 190/2 No additional 190/ shown under the key for the diagrams.

[18Fiatsandcounting]

late 2015 I printed a 1976 Spideer wire diagram from the Mirafiori library. I looked and now I don't see it as available.
This diagram lists 190/1 and 190/2 No additional 190/ shown under the key for the diagrams.

None of my diagrams explain a component 190/4 (or 190/3 for that matter), so I'm pretty sure the 190/4 in the M-B manual is a typo. It appears in other diagrams as well, so it's probably an error that got propagated over time. Almost all Fiat wiring diagrams have errors in them, but the most accurate ones seem to be the one in the owner's manual pamphlet.

-Bryan