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Look for a diamond-shaped black plastic body bolted to the transaxle. If you follow the speedometer cable from the cruise servo toward the axle, it's at the end. Unscrew the cable, unbolt the sensor with a 10mm socket and pull straight up.
 

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Vehicle Speed Sensor.
 

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RRToadHall said:
If I follow the speedo cable from the cruise servo to the transmission it goes into a white round, single bolt retention unit which is the speedometor pinion and looks nothing like the black diamond I received as a replacement. There are also no wires at that end of the cable.
That's it. It's a Hall effect sensor with a helical gear around the shaft. Undo the cable and bolt, and pull straight up (it's a very tight fit). Sometimes they could crumble, after all this time and heat exposure. The gear is not included in the replacement part, and so you transfer it from the old sensor.

Automatic or manual?
 

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I'll have to take a look at my car, should be the same. I know my analog speedometer is purely mechanical. Maybe the A/D conversion is done within the digital dash.
 

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Interesting. On the analog version with cruise, there is one cable from transaxle to cruise servo, and one from cruise servo to dash. I doubt that there is an A/D converter built into the servo, so if there are no wires at the speed sensor, and no cable to the dash, how does the dash acquire the digital input? Will check my 1984 service manual.
 

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Says it's inline in the speedometer cable, but the diagrams for the cable don't show it there. Will have to look at my car tomorrow.

And it shows a speedometer cable to the dash in all cases.
 

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Maybe someone with a digital dash can chime in. I'm wondering if this was a homemade custom conversion, originally analog.
 

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His setup is different. Speedometer cables were eliminated sometime around 1988 or so. On your car and my 93, the speed sensor generates a digital signal via Hall effect pulses, which is converted to an analog signal for our analog gauges, at the cluster. And so ours are not 'purely digital' because the end display is analog, as is the signal. His is purely digital, he has a digital dash. However, the factory manuals show a speedometer cable from transaxle to cruise servo, and another cable from servo to dash - regardless of whether it's automatic or manual, and it doesn't distinguish between analog and digital dashes. So that's why I wonder if he as a car that had an analog cluster, and someone wired a digital cluster in, with homemade wiring.
 
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