Hi, I have a 1993 400E.

It is shifting from 1st to 3rd gear. If selector is in position 2 it will not shift from 1st gear to 2nd gear, instead, it will stay in 1st gear unless I put it on position 3 where it skips to 3rd gear.

Remember 400E/E420's have 1st gear start. When it worked correctly when lever in position 2 it will start in 1st gear and shift to 2nd.
Now on positon 3 and D it will start in 1st and shift to 3rd. If I move to position 2 it will jump back to 1st gear. The only way to get it on 2nd gear is go above 50 mph and then move to position 2 and it will downshift to 2nd gear but REALLY soft.

Any help?? Will changing fluid/filter will solve this? or do I have a valve body issue? Vacuum issue?? Thanks!