Have had varying problems with the air suspension of my 2005 XJ8L. Replaced pump, front passenger and rear driver shock. Different manufacturer of shocks but all new. Pump also new. I know I have a leak. Both shocks on passenger side are low after setting for about 8 hrs. Upon start the front inflates but no change in rear. Back driver shock is noticably higher than passenger. Bad rear Height sensor, bad shock. Would shop diagnostic machine tell me ? Air suspension fault but no too low fault.