My 90 Loyale has a 4 sp auto and it will up shift to 3 rd and stay there, shift lever is in D and shows up on dash, but 3 rd also shows on dash. When I shift back to 3 rd or 2 nd it doesn't down shift. When trannie is cold it will act normal till it warms up and then it will down shift all on it's own and stay there. I pulled the pan and cleaned the screen. Couldn't find a filter. whatsup?

There arent many things that go wrong with a tranny thats cheap. Hopefully this is just a bad inhibitor switch. Sounds like the switch is borderline or needs adjustment, along with the linkage.

 

nipper