Auto box selector/ inhibitor switch

Hi, have a problem with a v6 auto, the dash display shows park no matter what position the stick is in. The park position light goes out when I move the stick, but does not show which position its in. The sport light comes on in the dash diplay, and on the stick in that position, but the changes are lumpy, the inhibitor switch does work. Have tried adjusting the cable, and checked the gearbox connectors all are good, auto fluid is clean and at level
Have seen f4 code flash up once. Try to kick down, it goes with a thump, often will go into limp mode. Any help appreciated

You need to get the codes read. It's pointless trying to guess faults like this.

try to get hold of Lord hippo he will be on landyzone some where he knows them inside out