I guess something could be going wrong on the other end. I replaced the speed sensor on the transmission tail and made sure the connector was in there good. I have since taken it out and put it back in just to make sure I installed it incorrectly but I am still getting nothing.

Ideas?

 

Are the rest of your gauges working fine? Check fuses, and the wires coming from the sensor to the gauge. Test the new sensor as well:

Remove the sensor from the tailshaft of the transmission and hook the two leads to a volt meter on the AC scale or if you have a digital meter with a frequency scale you can use that too. This will measure the frequency in HERTZ (Hz.),meaning cycles per second. Spin the little gear(probably nylon)as fast as you can by hand (drag your hand /arm across it real fast like you were winding up a toy car or top)and watch the voltmeter for a reading. If you get a reading ( a few volts or Hz.) it's probably still functioning. You could also turn the gear with a variablespeed drill.Keep it slow to be on the safe side.I'm guessing under 1000 RPM (most variables top out at 1250rpm for 1/2" and 2250rpm for 3/8"). If it won't go in the drill chuck (some gears have a little nub on the end you can grab),then wrap the gear with some tape and press the gear onto the side of the chuck,sort of like a bicycle generator on a bike tire.The tape will protect the little gear and help increase the friction between the two so it spins easily.

 

i would check the wiring under the dash. it runs from the ecm under the pass side dash to a white plug then from there over to the speedo. out of that white plug there is a gray wire that is your speedo wire.

the speedo is controlled by the computer(if you are reffering to the 1992 you have listed) so unless the computer took a crap its something in the wiring or the gauge itself

 

don't u have a speed sensor buffer? i believe on 92 only the tpi with the 7730 didn't had a buffer, the rs i believe do, its right above the ecm its a yellow box

 

the TBIs have a buffer, which now that i look at it i think he has lol, the v6 motors however did not have one as well.

when i did away with my ecm i had to put in a buffer box in order to get a speedo again

 

It is a 92 305 LO3 TBI.
All of the other gauges work fine. A little background: For years the speedometer would intermitently just quit for a few seconds and then come back. One day it quit and just never came back. Not sure if that helps or not.

 

u definitely should have a buffer box, take it of and test the C pin to see if u have any pulse thats for the speedometer
here is the diagram

 

yup ur right the v6 uses the 7730 ecm as well

 

Thank you for the diagram. How do I go about measuring the pulses?

I tested the old sensor with my digital multimeter. I could not get a reading usuing ac current and cold only get a .01 on the frequency

 

the car has to be moving in order for u to get readings since the buffer puts ot pulses per revolution, thats how the speed is calculated

 

I was referring to two different things in my last post sorry. Hw do I go about measuring the pulses sine it uses one pin? Do I put one probe on the pin and on on the ground and set the DMM for frequency?

Based on the diagram since my cruise control does not work it probaly is not getting a signal to the buffer.

 

i use a power probe so thats a lil different but yea black to ground and red to pin to test to get reading

speedo and cruse not working smells like the vss buffer is not working the way it should be

 

this will help u Vader explains it better than i lol

https://www.thirdgen.org/forums/elec...ss-buffer.html