Purple would be EGR temp sensor vacuum line, according to vac schematic my car's got on sticker attached next to radiator. Coulda been discarded there if replaced earlier.

An excellent thing to do is cut back vacuum rubber elbows and joints 1/4" to give fresh rubber that tightens up connections. Basically go from one to another with razor blade cuttin back rubbers and reattaching. You will see how it tightens em up with first one you do.

Returning to transmission, if fluid's overfilled even slightly then will shift harder than normal. Oughta be at bottom line on dipstick when cold, as I'm sure you know. I check tranny fluid level with car idling in gear and emergency brake on.