Hook it to the [ S ] stator terminal on alt. and be done with it.

 

Like I said earlier--"It's working just fine"--and I am not going to touch a thing. I am done with it. And-as it should.

 

Like so many I couldn't find a wire to hook up my electric choke on my 1980 Ford F-100 so I bought a switch and wired it up to the fuse box and now I have to turn the choke on and off.
I know it sucks but it is my only option for now.

 

I went with after market wiring from centec,,,,and when installing electric choke; I called Jim at Centec,,use direct wire from FP/GL terminal in your panel so thats what I did,,,,,might help somebody

 

Here’s my set up for solving the choke issue and other wiring. A fused 6 relay box.





1 - Sends 12v in Run (Distributor)
2 - Sends 12v in Run (Choke)
3 - Sends 12v to a fuse box to any accessories that need on with lights on. (Gauges, marker lights)
4 - Will be 12v always on (bed lights that turn on when the tail gate opens, horns, fog lights, etc)
5 - Will be 12v in run (things like daytime running lights I don’t want to manually turn on and off but I always want on)
6 - Empty for now but anything down the line like cooling fans.

Just to note I’m running a Pertronix so the ECM is removed.

I go battery to bus bar to fused relays then to accessory or fuse box. But you could go battery to fuse box to relays. I use the relays to divide the vehicle into its different states(Off, on, lights off, lights on, etc). Which makes the most sense for me and I avoid a rats nest of wires around my feet.

If I wasn’t doing a relay box I would just buy a single relay that could be screwed into the engine bay and sends fused 12v to the choke when on.

I also have the signal to the distributor relay on a kill switch in the cab so even if someone opens the hood and jumps the solenoid they won’t be able to start it or know it’s the distributor without time spent tracing wires.

For anyone interested, the relay box is by TrueMods on Amazon and I think for $20 extra they prewire all the relays which is super nice.

 

I checked every wire under the hood but found none that would work.
However, at the fuse box the one for the radio might work, its hot when key is on and off when key is off.

 

The wires going to the ECM in the engine bay. One is key on. I don’t have the wiring diagram in front of me so I can’t tell you the color. You can disconnect the plug and test which one it is. This is the one on my ‘78.




However, I would only splice off that if you’re going to use it to send an on / off signal to a relay. I wouldn’t actually draw off that wire. I believe that wire has a resistor in it.

I ran my choke off the radio until I got to rewiring. It’ll work well enough but I would still recommend cleaning it up down the line.

 

 

I'm looking at wiring into the radio fuse too, thanks for the suggestion!

 

I spliced into one of the wires going to my duraspark. Swapping to HEI distributor so these wires weren’t being used anyway. One is 12v on crank and the other is 12v on run. No resistor on that wire.

 

Sounds good but I'm dealing with a 1980 4.9L, not a lot to select from under the hood.
I've been looking for the original wire with no luck.
I guess my best options are to stick with the switch I wired in or go to the radio fuse at the fuse box.

 

There are quite a few differences between the 73 to 79, and the 80 and later trucks. Lots of wiring changes, but one thing should have stayed consistent. If your truck had a carburetor with an electric choke, there would have been a white with black stripe wire somewhere near the carburetor.
That was the original choke wire from the alternators stator post.
It’s only powered when the engine is running. Doesn’t matter what position the key is in, the engine has to be running and the alternator has to be charging.
There should be other wires you can tap into as well, that don’t affect the ignition. Personally, I would never connect an auxiliary device into any of the ignition circuits. Unless, like the previous situationition mentioned, where the Hei was installed, and the original ICM was no longer used.

One that comes to mind is the green with red stripe wire to the voltage regulator. I prefer not tapping into that either, but for me that’s better than the one to the ignition.
And many people are converting to later model alternators now as well, so often that wire is no longer used. But it’s at least one of the few wires that is hot with the key in the ON position, and not the ACC position.
This means you can sit there and listen to the radio and not have any effect on the choke.

One thing I saw mentioned at the beginning of this thread way back when, but did not see answered, was the reason for the 7V reading on the “I” terminal of the starter relay.
That’s because there is no voltage coming from the terminal itself, except when the key is in the START position. Otherwise you’re getting a reading through the resistor wire from the ignition circuit. But only when the ignition switch is in the ON position.
That’s why the reduced voltage reading sometimes.

 

I looked but couldn't find any wires that were factory.
I have an extra fuse box installed so I hook up a switch to the choke and turn it on and off manually.