so, I have a 2004 Allroad. Recently, my rear suspension has been acting up. I push the button to raise it, the front is fine but I can hear the back trying to raise it, but it never does. If I go over 55 mph the car drops to level 2 and the back end bounces like crazy. I stop, turn the car off , raise the suspension drive under 55 and it's fine. Any suggestions as to what it might be? Thank you

 

Is the compressor running fine? Also, try to check the airbags for leaks.