I know this isn't ZHP specific, but thought I might get some input here also.

I picked up this '02 325i this weekend that was for sale due to the transmission being in limp mode. Reverse works fine, but when you select drive and start moving forward it almost immediately goes into limp mode. The recurring code is 33 Turbine Rev Sensor. I connected my laptop running BMW INPA to it last night, and I am getting erratic readings from the turbine sensor while the car is in Park or Neutral. It should be a steady figure that is only slightly less than engine RPM, but as you can see from the below video it is erratic.

https://youtu.be/amyYULb-dsw

My first guess is that the input speed sensor inside the transmission is failing, or the wires to it are shorting/frayed. I guess it could be a slipping torque converter, but then I would imagine it wouldn't work in reverse either. I can at times use manual mode and it will drive fine for a short bit, but then will go into limp mode again.

I plan to pull the pan and check the fluid condition, as well as see what other material I might find in the pan. Does anyone have any thoughts, comments, or suggestions to help pinpoint that this might all be related to a bad input sensor?