Need Help Air Suspension

[Drop the Puck]

Hi All,

Need suggestion and advice on what to look for. I am stumped

I replaced both rear air bags, new o rings on fittings
replaced valve block, again new o ring and fittings
Sprayed with soapy water to confirm no leaks, all good!
Started BMW air bags filed to 31.5 inches all good, but then they start to deflated equally after about 5 mins.
Checked for leaks again, found none., Where should I be looking, maybe sensors telling bags to deflate? Is possible compressor has check valve that's failing ?
The air bags are not leaning on side or another but equally deflating at same pace??

Any advice appreciated
2009 X5 E70,

Thanks in Advance!!

[Vitalität]

Is the compressor loud?

[Drop the Puck]

Little louder than usual, takes a while to inflate bags say " 1-2 mins min." then after bags inflated within 2 miles get a warning..suspension level failure

If your thinking compressor. You might be right, but wouldn't the valve block stop back pressure leaks?

[Vitalität]

Same thing happened to me and compressor was loud and takes longer than usual. Also, after turning off the engine, the compressor remains loud for almost a min then stops. I replaced it with a new arnott compressor and the issue went away. Didn't have to deal with the valve block or anything. Seems like in your case, the only thing you haven't replaced is the compressor so that could be it.

[Drop the Puck]

I agree, I was hoping not to have to replace the compressor as its more than air bags and block combined. I was looking at air to spring coil conversion kits yesterday by suncore, going to look hard at it again today. The only issue I think would be how to delete or shut off suspension level system warning. If converted back to coils no more issues with air suspension..
What do you think

Thanks again

[Vitalität]

Yes you can do that conversion and you just need to delete the warning by having it coded. There are independent coders out there that can do that. There is set of coilover for sale right now in the classified section if you want https://www.xbimmers.com/forums/show....php?t=1547223

[Drop the Puck]

Thanks I really appreciate all the help, I am seriously looking at the spring conversion....No more head aches with air suspension. I am usually GM person, this was my first BMW...

Keith

[Vitalität]

Originally Posted by Drop the Puck

Thanks I really appreciate all the help, I am seriously looking at the spring conversion....No more head aches with air suspension. I am usually GM person, this was my first BMW...

Keith

Air suspension would last for a while though. The Arnott ones which I have both compressor and air bags, have lifetime warranty. I was driving a GM vehicle with LS2 engine before and thought I would be loving it forever but went back to BMW. It was a TB SS.

[Drop the Puck]

Ordered the conversion kit from Suncore, found a person who did coding/scanner went through all possible faults and error codes. Seems that compressors at about 75-80 thousand kilometres start to fail. From what I understand a Nylon-Graphite piston ring wears down either not applying enough pressure or leaking. Vitalitat, you where right it was compressor. I will leave everything except air bags in place , covering air line ends and fittings just in case I ever decide to change back...better safe than sorry, you never know might run across newer compressor one of these days. I will however post my experience with the conversion kit and the install.

Thanks for all the help. I really appreciate everything.

[Drop the Puck]

Hi All,

Replaced rear air suspension with coils spring conversion kit. First I bleed the air lines at valve block and unplugged in order that compressor did not kick in. Placed on safety stands and removed ai bags. I left the fittings on the lines, used wire meret " plastic wire connector" that fit snugly over the fittings as to protect in case decide to go back to air suspension, used electricians tape for added protection and placed securely out of way. The I unbolted shock mount at suspension to allow more movement. I found that my Macpherson coil spring compressor was to big. Had a friend come over about "200 pounder" to stand on rotor and press down, doing little bouncing movement. This allowed me to fit coil spring in directly without spring compressor. After fitting both side with new coil spring conversion kit, used floor jack under rotor to move suspension back up allowing me to reconnect the shocks. Took little over 2 hours total. When finally assembled, tighten air lines at valve block, plugged power line back in. I took for ride to make sure coils springs seated well. The ride is great, truck sits at 31.5 inches from bottom of tire to upper wheel rim. The only issue I have had so far is a warning " suspension level failure" which I understand can be coded out with a scanner/coder BMW specific.....otherwise all Good.

Hope this helps

Drop the Puck!!

[heatmizr]

Drop the Puck -
How did the faulty piston in the compressor cause a leak? Doesn't the Valve Block sit between the compressor and the lines to the airbags?
I have a similar issue, thinking its the valve block or the vent valve. No idea if I can source those separately.
Been a while, hope you still remember!