Unplug the connector on the side of the trans. Do you see red fluid? You shouldn't see any fluid at all. The connector is known to crack internally allowing trans fluid into the connector. This will cause a host of issues with shift/ing.
You'll need to drop the pan and replace the wire harness internally. Easy DIY. While in there change both Shift solenoids and turn up the force actuator a 1/2 turn. New fluid and filter as well.