93 DX speedometer problems

I've gone through a bad speedometer/gauge cluster a couple of years ago on the same model civic and took care of the problem with replacing the gauges, anyway my current civic is doing the same thing. However this time the speedometer is not working when the car is cold, after it has warmed up and running speedometer is normal.

In hopes that it is not the gauge I am thinking maybe the problem is at the sensor because that is where the temperature differences around the motor would be effecting it.

Does anyone know whether or not there is supposed to be lubricant/grease/oil on the sensor where it makes contact with the trans?

I am guessing no since I detect a light tranny fluid odor from it.

Anyone have some insight into this?

Thanks