Chevrolet Repair: Automatic transmission does not work & electrical problems, vehicle speed sensor, transmission gearbox

Question
Hi, I have an Bazer 10 1994. The automatic transmission does not change gears. It works perfect to use "manually" but it doesent work "automatically". I took it to a transmission specialist who simply said its not a mechanical problem with the transmission (gearbox) since it works manually. Otherwise it would "default to gear no 3 in a "take me home mode". He thougt it was more "electrical" with some sensor or something else in the electrical system that didnt provide the gearbox with proper info. There is also several other electrical problems with diffuse/hard to solve problems, like ABS, interior lights, panel lights etc
Best Regards¨Joakim  

Answer
Hello joakim,
This could be very hard for me to try to help with that assortment of problems, and not being able to see it.
But there is one thing that could have an effect on several of the systems you mention.
If that has an electric shift transmission, and the vehicle speed sensor is not working, it could effect the shift, and also the ABS, and cruise control. The speedometer should also have problems.

If it is not electric shift, meaning there isn't a big electrical connector on the side of the transmission, then the shift governor could be stuck, or the throttle valve is stuck. But it sounds like the shift governor. It is bolted to the right side of the transmission, near the rear. About half way up the side. A little cover can be removed, and a assembly can be removed, cleaned, and checked. it controlls oil flow to the valve body according to driveshaft speed, moving a valve in the valve body to downshift as the vehicle slows down.

Good luck on that, and the rest.

Van