Self levelling issue….(!)

[svvg]

Hi - I’ve got a strange issue which I think I know the answer to, but interested in others thoughts please.

I have a 2004 4.8 X5, with dual axle air springs. I rebuilt the pump with a “bagpiping andy” kit a few years ago, but recently have an issue with the dreaded “self levelling inactive” error message again (the code states accumulator fails to fill on demand…”.

I initially thought I had a weak battery, as I had this issue before, and it caused the same error - using the “hidden” menu on the dash my voltage seems to drop below 12v and keeps falling. I replaced the battery, but the same problem persists. I also hooked a charger up, and left it attached. Each time the code will clear with INPA or dis, but it comes back on as soon as the car moves.

Now the odd part…. The accumulator shows 12.2 bar each time the system fails. If I run the car and then clear the codes with the engine running, the accumulator will then fill to 15.5 bar (I think it goes to 15.5….), and it’ll all work for a few days again….

My thoughts on this are that the pump is worn again, and hence running, but is weak. With the engine running it gets the extra kick of voltage (up to 14 ish) to make it work that bit harder in order to fill the accumulator…????

I am not convinced by my own logic - but have ordered another rebuild kit, as they’re only £25, but if anyone else has any insights I’d be very grateful.

The car doesn’t sink or sit too low - so no obvious air leaks - and sensors and pivot arms on the sensors should be ok, or it wouldn’t work for the day or so in which all is well…

Many thanks for any suggestions.

And does anyone want a near new yuasa battery which I didn't need to buy…. Cost me £140! Bgger.

[Clavurion]

I would say that unfortunately this sounds more like failed control unit. For some odd reason it's not always activating the compressor properly to make that filling of pressure accumulator.

[EODguy]

Originally Posted by Clavurion

I would say that unfortunately this sounds more like failed control unit. For some odd reason it's not always activating the compressor properly to make that filling of pressure accumulator.

+1

I swear that mine was eating control units so I swapped to coils after 5th or 6th one. Never figured out what was going on but since I could only get used ones here....

Stateside there are several places to send of for repairs. (so I'm told)

Sent from my SM-A528B using Tapatalk

[svvg]

Ah thanks - And ah sh*t! They’re £700 or so here I think…. And that might be for used units. Will see if the rebuild kit does anything for me - and then if I can source a used/repairer in the uk…

[Clavurion]

Originally Posted by svvg

Ah thanks - And ah sh*t! They’re £700 or so here I think…. And that might be for used units. Will see if the rebuild kit does anything for me - and then if I can source a used/repairer in the uk…

Or take a bet with a used unit.

https://shop.euroimpex.lt/en/dalis/6...odule-airmatic

[svvg]

That’s pretty cheap and worth the bet… will rebuild the compressor again as the kit’s only £25 (and ordered) and see. Thank you for responses!

[apvilla72]

check again your pump piston and cylinder....i replaced mine with the same kit and its still working...i had the same error...its been almost a year

[svvg]

Yeah. Will do. I don’t think you can get the cylinders any more (just the piston ring seal kit)?

[LA02MAX]

For what it's worth, and I'm sure you've heard the suggestion before, but I swapped to coils after I was showing similar symptoms. I didn't want to just throw parts at it without knowing the cause. I used OE sach's struts/shocks with lesjofors springs and all OE mounts/hardware from FCP euro and I honestly can't tell a bit of difference in ride quality between this and my air suspension. No more worrying about one of the many suspension errors that can happen to disable the vehicle when I'm miles away from home.

[svvg]

Mmm. I kind of want it to work ”the way it should” - but I hear what you’re saying. I have a piston rebuild kit and will see if I need a cylinder kit too. Then I guess I’m looking at control units….

Another current and major issue is the massively wayward steering - recently changed the tie rods and ball joints - but I’m pretty sure it’s the steering coupler (and possibly the rack itself).