Unplug of odometer at transmission?

[ZEUS]

As I showed a mechanic/friend of mine my new baby, a 95 rt with about 15kmiles, he joked that maybe they unplugged the odometer. He was joking as my car shows mint, but made me think that could this be possible? He suggested that though the computer would record official mileag (whether or not the back of the speedometer was unplugged), that neither would register any mileage if the speed sensor was unplugged at the transmission. Is this true? I know it has a pulse sensor(?), but is it this that sends the signal to the computer for recorded mileage then to the speedometer/odometer itself? Can it be so easy....should I be so nervous?

 

[1TONY1]

I don't think a 95 would record the mileage......to much pcm swapping going on with gen2 cars, I don't think they retain mileage either. You are correct, the odometer gets the info from the tranny via the pcm.

 

[Asp Man]

You can try it, but I doubt the car will run well. Speed density PCM mapping (ie: no mass airflow sensor).
The speedo (at least on a Gen II) is not the only thing looking for a signal from the speed sensor.

 

[SingleMalt]

VERY VERY bad idea. The reverse lockout will not function as it does not know when your car is in forward motion. Could be a real scary shift at high speeds.

 

[1TONY1]

Guys....I don't think he wants to unplug it. He was curious if it could have been previously done to keep the mileage low.

 

[Randy]

This was just discussed in another thread, I'll paraphrase what I wrote there:

Its trivial to unplug the speedometer signal from the dash - you lose speedometer function, but it also no longer increments the odometer - so, mount a GPS to the dash. The Gen I PCM does not record mileage, according to a Viper tech I trust, the Gen I PCM only records total time turned on (???). So, you can supposedly read the total time on and see if that generally corresponds to the odometer (figure some average speed, say, 30 mph, and if the PCM says 1000 hours and it only has 500 miles on, there's likely something wrong).