Suspension dropping X5 4.8is only in cruise mode.
 

Hi fellows,
i'm experiencing a weird problem. My 2006 X5 4.8is with all four airsprings have a problem i'm not being able to solve.
There are three suspension modes:
off road, cruise and access.
When in off road mode, low speed (below 55 Km/h) the suspension remains in this mode, without problems, for miles, parked and so on.
As soon i reach cruise speed, more them 55 Km/h, the suspension goes into cruise mode, and after some time i can hear an air hissle at the right side, the right front suspension begins to drop, then the left front suspension drops, loosing all the pressure, and the car starts bumping like crazy, while the rear airprings remains in the correct cruise height. Slowing the speed, and selecting again off road mode, the suspension lifts and all normal again. Sometimes the system gets in protection mode (i guess because is overheating), not acting until i stop and wait for some hour, then it works again.
As it shows up, there are no air escape from the bags or airsprings, the compressor is working right, because the pressure remains while slow speed and parking.
Did anyone from you got this problem and knows how to solve it?
Thx in advance for valuable help.
PW44

Bump... No ideas? :(

well, when you put it in offroad mode, the pump is filling the bags with air so it make sense for it to get "normal" unless it has major leaks in the system or other major issues.

What height do you have if the vehicle sits for long period, for example overnight?

I just replaced both front bags on mine. The left side would get low sometimes, then it started getting low more often. I was going somewhat a far distance one day and the suspension blew completely where it wouldnt pump back up. $1000 later front suspension is good as new. Thanks to Arnott.

Sounds like you need recalibrate if its going that low.


To test if bags are good, put it in offroad mode, measure ground to fender height, park it overnight leaving it in the offroad mode and visually may be able to tell or measure if its leaking.

Thx for the answers.
When in offroad mode, it mantains this mode with no lowering, parked for more than one day. When driving bellow 55 Km/h, it also maintains the offroad mode.
The problem is when it return to normal mode, driving, than it begins to lower until the front looses all pressure., so there are no leaks in the bags.
The air hissle i hear comes from under the car, right side, when in normal mode, driving. Leaving parked in normal mode, it maintains the height.
Any ideas?
Thx in advance.

Note that the car wont maintain to offroad height when driving above 55kph. It will drop to the normal height. But if you mean that car drops all the way down - even lower than access mode, then there is indeed a problem.

Check your pressure accumulator which is under right side of the car. I guess that the pressure accumulator is gone and you need to replace it. By the way, since both of your front air struts have been running without air, so you have to replace both of them. The struts are all gone too.

Thx for the answer. Two questions:
- why do the struts maintains pressure in off road mode?
- why do the pressure accumulator looses pressure in normal mode and not in off road mode?
Does anyone knows how does it happens?
Thx in advance.

You really need to hook up to DIS/GT1 to read any faults in the module before you start replacing parts.

since you said you heard leaking sound from the right side, so it must be somthing wrong with the pressure accumulator. I guess there is something wrong with the accumulator when it holds at a certain pressure level. Also, it could be the pressure sensor or the valve unit. I think mostly like the pressure sensor or the valve unit goes wrong.