F15 Air Suspension Issues

[tamiller512]

Hi all, long time BMW fan, first time poster here. I really appreciate the wealth of knowledge that is here on this forum- it is a very useful tool! I have had several BMWs through the years but have always leased while the car is under warranty, so never had to worry about when something went wrong. However, we recently purchased a 2014 X5 xdrive35i, and of course 2 week after purchasing it, I am having rear air suspension issues. I think I have read every post regarding air suspension issues on this forum, and none of them describe the problem I am having.

The car has been great with no issues over the past 2 week. Yesterday, the car was off and sitting in the garage. The rear end was at a “normal” height. I opened the door to get something out of the car, and the car of course “woke up.” Immediately, I heard the hissing of air and both sides of the rear end deflated completely within 15s. I heard the compressor kick on, and nothing happens to either side of the rear. The compressor timed out after about 20s. I started the car, let it idle for a while, and neither side inflated. Every time the compressor kicks on, I can hear the hissing of air like there is a leak somewhere. It sounds like it is coming from the left rear somewhere.

The car has just under 80k miles on it, and I have access to the full service history of the vehicle. Both air struts were replaced in Oct 2020, the left one was replaced again in Sept 2021, and the air compressor was replaced in Dec 2021. Sounds like a habitual problem. Anyone ever seen anything similar? Any idea where this leak is coming from? Thanks for any help!

[acmurda]

sounds like loose air fitting or air line popped off.

[tlow98]

Yeah jack it up and take a look. The system is actually very easy to service and remove.

[5tony]

Strange that they deflate suddenly after waking the car up. I replaced a leaking bag on my car and it still deflated after a a few hours of sitting. Finally had to clip a half inch off of the air line, where it attaches to the bag, to then put the hardware back on to the line. That finally fixed the leak.

[///d]

Originally Posted by 5tony

Strange that they deflate suddenly after waking the car up. I replaced a leaking bag on my car and it still deflated after a a few hours of sitting. Finally had to clip a half inch off of the air line, where it attaches to the bag, to then put the hardware back on to the line. That finally fixed the leak.

It's likely that the OP waking the car caused the system to open and attempt to inflate the bags to operating pressure, and a line was already weak and about to give and it finally did. As lines get older they get harder , inner diameters get stretched, etc and the seals they create get weak, and eventually they will start to leak. Thats why you cutting yours back a little worked, you removed the stretched out inner diameter.

[acmurda]

especially since op mentioned everything has been replaced, that leads me to believe a fitting or something was left loose

[tamiller512]

Nope, airline didn’t come loose from the fitting and it wasn’t the fitting itself unfortunately. Bought a new fitting and same problem. I guess it’s the bag, even though it is a year old? I just ordered a set of the Arnott bags. Fingers crossed they will fix the leak…

[acmurda]

Originally Posted by tamiller512

Nope, airline didn’t come loose from the fitting and it wasn’t the fitting itself unfortunately. Bought a new fitting and same problem. I guess it’s the bag, even though it is a year old? I just ordered a set of the Arnott bags. Fingers crossed they will fix the leak…

it's unreal how bad oem bags are. I replaced with Arnott n so far so good. The amount of threads about this issue is insane, given its such a simple pneumatic set up, the weakest link is almost always the bags. Good luck, hopefully it get sorted with Arnott bags for ya

[cfm56d7b]

Joining this thread. Rear air springs failed on my 2015 X5 with 33K miles. Just replaced both (right rear one failed).

Air supply unit is still OK.

[///d]

Originally Posted by tamiller512

Nope, airline didn’t come loose from the fitting and it wasn’t the fitting itself unfortunately. Bought a new fitting and same problem. I guess it’s the bag, even though it is a year old? I just ordered a set of the Arnott bags. Fingers crossed they will fix the leak…

Depending on how long the bags you used the first time were sitting on the shelf, they could have already started to dry crack. Or you were just unlucky to get a defective one right from the manufacturer. It happens. Arnott bags are good though and you will likely not have anymore issues with those.