XSeries-forum

Here's a question for the experts among us...

In two previous X5's i've had, the rear air suspension would fail & one or both rear corners would sag.
So, as I worked for a company that made the rear Air-Suspension bags, I "procured" a couple of 10cc syringes of the O-Ring silicone lubricant.

The air pump units of these previous vehicles has a pressed brass ball intake filter to prevent dust n crud entering the suspension air system.
I would remove this & ease some silicone lubricant into the intake as the suspension re-levelled itself.... & Et Voila - Problem never came back, as the goo would nicely coat all the valve seals etc.

Well, the same occasional saggy issue is occurring with the current X5...

So, I have got the air pump unit in my hand & I cannot see any hint of an air intake for the pump, only the exit tube to the valve block.
I was hoping to put a splash of lubricant into the system to seal up all the O-Rings & seals, but there is no-where obvious that is the air intake.

I did spot & open up a white plastic cover with a couple of springs in it, but no bores or anything inside the bore there.

Where does the air GET IN the air pump .... it needs a hole or filter to get in.... it cannot get into the pump by magic !!

Very puzzled, as it should be obvious..

regards to all.
Grant B

Update - after spending all afternoon tinkering & squeezing silicone juice anywhere & can squirt it in valves & tubes etc....
The left rear is still wanting to begin sagging after 30 mins with the vehicle sat idle.

Note I pulled the relay at the valve block to disable the pump when playing with it & replacing to enable again....

I DID NOTICE that while the pump & valve assembly was open to see the pump unit & in pieces & jerry rigged to work,
a couple of things happened...
1 - there was a hiss from one of the valves for 20 seconds after it had stopped pumping & levelling the car...
2 - the levelling system would not re-boot until the battery was disconnected & reconnected, then the ignition turned on at the keys..
I do seem to remember this happening with a previous X5 needing the battery disconnection to get the suspension to talk to the car.

I stuck my head in the wheel arch & can hear nothing from the air bag, (both of the rear air bags were replaced 5 months ago)

So I'm guessing a Leaky Valve Block, & another afternoon with the car in bits... unless any one has any better ideas ?

Update No 3...
The Left Rear corner was sagging..... some times..
So, I replaced the valve block, swapped out Both Airbags, checked all the pipe joints with soapy spray...

And the left rear corner still sags

I am wondering where the control modile lives...
Anybody know ?

Should be here:
Is the level sensor OK on that side?

Many thanks chap.
I have a spare sensor for that corner, So will swap that out tomorrow too.
Have a great weekend.