Speed Sensor Problems? [1987 Ford Bronco II]

[Nelson and Hudson]

Hello, this is for my 2.9L 4WD B2. Currently, I'm having issues with the car stalling/dying. I replaced the wires, distributor, and ignition coil and wire. After replacing the ignition coil and connector it seemed to have stopped stalling while at freeway speeds, it continues to do so cold at low speeds around town. I am almost certain it's an electrical issue and not a fuel issue due to how sporadic it is. It may be a vacuum leak, so I'm building a smoke machine to smoke it out. While hunting down broken wires I came across this guy, looking online I found that it was the speed sensor (https://rb.gy/v0vya). I found this part from O'reillys but not the connector itself which is what I think is broken.
Where can I find the connector for this? (What are the wires themselves measuring?) Could this be causing me my stalling/dying issue?
If you have any other advice I'd appreciate it, as I'm still learning about cars and am trying to expand my knowledge. Thanks.
-Hudson

 

[franklin2]

The speed sensor tells the computer the road speed of the vehicle. The computer uses this to decide if it should use idle fueling strategy or running down the road fueling strategy. So it could possibly cause some idling problems, but I do not see it causing stalling running down the road unless it completely shorted out something.

You can see in the photo it still uses a mechanical speedometer. Later on (1993?) they used the speed sensor for the electronic speedometer and the abs system also which your vehicle doesn't have.

 

[RonD]

I assume your speedometer works, does read way off or drop out now and then, so the gear drive is OK

The 2 wires are for the VSS sensor that reads a spinning "tone wheel" inside the housing also driven by the same gear set
A VSS generates its own AC voltage signal, so not a "powered" sensor
It generates an AC Sine wave with 16,000+/-ppm(pulses per mile) but signal is Grounded so 8,000ppm is the output, this is/was a Ford standard for many years, 8,000ppm
The AC Voltage, 0.5vAC to 8.0vAC is not used, just the Sine Wave pulse
It was added when computers were first being used in engine control, in Rangers 1985 or so
It was also used for Cruise Control vs the double speedometer cable setups

You can pull out the unit and hook up a drill to it and test VSS output with Volt Meter set to AC Volts, faster spin higher AC Volts

While volt meter is set for AC Volts, lol, you may want to test your alternator for AC Ripple
Alternators generate AC Volts, hence their name, and Diodes are used to convert the AC to DC Volts, if a diode fails then some AC Volts can leak out and that can/will cause issues with several systems in a vehicle
Easy to test for AC Ripple