hey I got a 2001 a4 auto tranny 2.8 awd its throwing a p0706 code witch is the transmission range senor. I replace that also along with trying a new tcm an ecu but nothing help. at frist it would only do it when the car was on for 20 mins to an hr then all the time now. time to time it come out of limp mode an runs fine for hrs even days some time. when it goes back into limp mode the gear selector reads P when im driving or N an wont let me do pass frist gear ...this is killing my gas milage an wallet please help

 

Have you run through all the potential water leak areas (lots of opportunities with the sunroof and plenum drains)?

I have a manual so it's tough to know the exact error codes, but I've spent plenty of time in limp mode. If it's something that seems to go in & out for days or weeks, then come back - it could be related to rain and water all over your electronics.

If that's not it, then best of luck searching.