My 2002 has been sagging on the drivers side rear- usually overnight, sometimes never and sometimes on the bump stop. Just on the drivers side though. Ive been over the most of the system with leak detector (soapy water) several times, including the air bags, accumulators and lines but never found anything.The bags where new Arnott items recently so didnt really suspect them, but checked anyway. Then I had an idea... the air to the bags is controlled by two valve one left and one right, 5 minutes of easy spannering and I swapped the airlines left to right along with the electrical connects. This should prove if the valve is dicky as in theory if the other bag goes down now, it must be the valve at fault. Sure enough next morning she was leaning the other way... now to find a pair of replacement valves. I spent a good couple of weeks trying to find a source for the valves but they only seemed to be available as a complete pump valve assembly at big money so looked at a tangent to other vehicles with similar setups. Comming from a Range Rover background a quick scoot around the Land Rover marque led me to the MK2 Discovery...
This is the Discovery valve block.
Compared to the original X5 unit
Location of the valves in the turtle shell..
I can report that this has worked a treat and at £30 for the DIsco valve block from our favorite auction site, a nice cheap fix.
Took mine to my local indy to be told to go to the bmw as they have no clue.
The checked the bags and they we're fine its th o/s/r that goes down when I have passengers in the rear.
Could it be my valve too?
If so would the disco unit work on an e70?
Thanks
Have another potential fix-it for this OCCASIONAL suspension sag issue...
I just detailed the same issue in the General Column of E53.
I discovered it is possible to re-lubricate the O-Ring seals of the valve block.
Read the article, and mail me privately with your postal address for a few cc's of the manufacturers Silicone Seal Lubricant...
Note... any old Silicone WILL NOT WORK... the chemicals in the lubricant are very specific.. hence using the right stuff.