92 automatic not shifting on its own

[riogrande4x4]

My 92 has been running excellent for about a month now since I purchased it. I recently took it on a 2.5 hr road trip (75 mph) and it sat overnite and the next day I went to drive it back. No shifting what-so-ever. Tranny fluid is fine and not burnt. I got back into it and drove it for abour 2 minutes and it started shifting by itself. I managed to stop for gas and shut it off and it worked fine once I got back inside.
Monday morning I got in and drove off...only 1st again. I put it in 1st and manually shifted to 2nd, but 3rd was neutral and 4th=1st. I parked it and drove my CRV instead. When I got home after work, same issue. I drove it for a few minutes and manually shifted it and she came back to life.
Tranny going sour??? There is no slipping when driving? Electronics?
No idiot gauges going off either(O/D light not flashing)

TIA

*edit* I just did a lot of searching and found that my gov may be sticking. I will try cleaning it up and doing a fluid and filter change while I am down there. Hopefully I am on the right track...

 

[riogrande4x4]

I cleaned the govenor a few days ago, but it did not fix the problem 100%. It actually shifts better, but I still have to maunally do the 1-2-D-OD shift...this time only once before it starts shifting on its own as opposed to having to do it for about 2 minutes. Perhaps its time to go to the stealership and purchase a new one? Any other suggestions? Anyone?

 

[Glacier991]

Check the vacuum modulator. Pull the line and check for ATF. How is the ATF and levels ?