97 Lumina Speedo

[typerx7]

Where is the speed sensor located on a 97 v6 Auto? And how hard is it to replace yourself?

[Blue Bowtie]

Presuming your Lumina has the common 4T60-E transmission, the VSS is located on the rear of the transmission, slightly above and behind the RH axle output shaft.

Replacement is a matter of gaining access to the underside, removing the electrical connector, removing a cap screw and clamp, removing the sensor, cleaning the surrounding area, oiling the O ring seal, replacing the sensor, and clamping/connecting the new sensor like the original.

You may have to install the plastic driven gear on the VSS onto your replacement sensor, or may find that the plastic gear is damaged, requiring replacement.

[typerx7]

THank you for the info. Just to clarify, by RH you mean passenger side?

I will tell you the problem that I have been having and you can tell me if I am write in assuming it is the VSS.

The speedometer does not function properly, erratically changing speeds, up and down, up and down. I assume that the changes cause the transmission to shift up and down, no matter what the actual speed the car is traveling at.

So I assume the VSS is busted. Other than that, the transmission shifts smoothly. The throttle is smooth and responsive as well.

Any other ideas?

thanks again.

[Blue Bowtie]

RH = Passenger side (on a domestic vehicle).

Does the cruise control function follow the speedometer indication?

Is the "Check Engine" lamp on during driving?

If the transmission (specificallt, the TCC) and cruise functions are also erratic, there is likely a problem in the VSS circuit. There may also be mechanical damage to the VSS driven gear.

You can remove the VSS and inspect the gear and its connection to the VSS spindle. Inspect the electrical connector at the VSSD and the wire harness nearby for damage, since there may be exhaust system interference. Beyond that, test or replace the sensor.

[typerx7]

Yes, the check engine light does stay on while driving. I haven't had the codes read yet to see what the exact problem is.

I have also had problems with the cruise control as well. That has always been bad since I purchased the vehicle from a friend two years ago. Up until now, I haven't had a check engine light or any other problem with the vehicle, it has been quite reliable for a chevy with 175,000 miles on it.

I'm not so sure that the 97 Lumina, or at least this model ( 4 Door V6, LS I believe) has a speed sensor with the gear attachment. The sensor seems to be reading magnetically; as the tip of the sensor that I pulled out is magnetic.
There is no sign of another piece that broke off. This is a weird sensor as all my other vehicles, 95 and older, have the sensor with the gear.

I searched for pictures online and they all show no gear; must just be an advancement in speed sensor technology, possible more reliable.

Thanks again for all your help.

[typerx7]

Ok... SO i went out and bought a new speed sensor, replaced it and it didn't change a thing. The speedometer doesn't work at all now, and the check engine light and security light are on (on previously)

Is there a trick to resetting the ECU?

I have already tried pulling the + battery cable from the battery, waited a couple of minutes and replaced it....nothing...

Thanks.

[Blue Bowtie]

No real trick - You might have to scan for DTCs and find the root of the problem, then clear the stored codes via the scanner.

You can check the circuit continuity between the VSS and the PCM to make sure the circuit is intact. The PCM conditions the signal and sends a pulse train to the speedometer and cruise control module.