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Discussion Starter · #1 ·
Hello all,

My 2016 740i just started having issues where the right side of the car drops down when the car sits overnight. After the car starts and I start to move, it raises back to the normal height. Wondering if anyone could give me an idea on how to troubleshoot this issue?

Thanks for any help.

-David
 

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Does both the front and rear of the right side go down, or just one corner? If it's only one corner, see if the strut or air line is leaking. If it's the entire side, the chance that both struts failed together is low, so the issue is more likely to be with the valve block. Leaks can often be identified by spraying soapy water and looking for bubbles.

BMW does not sell the valve block separately from the compressor, but you may be able to get an aftermarket replacement.

 

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Discussion Starter · #3 ·
Does both the front and rear of the right side go down, or just one corner? If it's only one corner, see if the strut or air line is leaking. If it's the entire side, the chance that both struts failed together is low, so the issue is more likely to be with the valve block. Leaks can often be identified by spraying soapy water and looking for bubbles.

BMW does not sell the valve block separately from the compressor, but you may be able to get an aftermarket replacement.

It's both front and rear.

I'll try the soapy water but I agree, it's unlikely that both front and rear fail at the same time. It appears the compressor is $1000+.
 

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Robin750,

Is this what you are referring to:

Correct, that is the valve block.

If you look at the RealOEM link in my previous post, you'll see that cars built before Aug 2016 use compressor part # 37206861882. I assume yours is before then since that date seems to be SOP for MY2017, which uses compressor part # 37206884682. Not sure if the valve blocks are interchangeable between these parts since that link only lists compatibility with the newer part.
 

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Sounds like you've done this repair? Was it difficult?
I haven't had any issues with the air suspension but there have been a couple threads about it on the F01 and G12 boards. The F01 only has single axle air suspension but the G12 has dual axle, so the systems are not identical but you may find some value going through those threads too.


 

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Is it accessed from the trunk or under the car?
Underneath.

BTW, I just checked the replacement steps in ISTA and the compressor is located in the rear left corner of the car. You may be able to get some access by removing the wheel and wheel liner, but if that's not enough, you may need to remove the exhaust and exhaust heat shield.
 

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A quick update..

Just purchased a floor jack last weekend. Going to buy the valve block and try to install once I receive it.

I noticed that the side affected occasionally makes a quick and loud hissing noise (about 2 sec long), and repeats a few times before it stops. The best I can tell it happens only on the back wheel and does not happen all the time. Could this still be related to having a bad valve block? The actual pump seems to work fine.

Oh, I also get a chassis error that only says I can keep driving normally but should have it looked at. I'm assuming it's related to right side of the car not being stable.

-David
 

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A quick update..

Just purchased a floor jack last weekend. Going to buy the valve block and try to install once I receive it.

I noticed that the side affected occasionally makes a quick and loud hissing noise (about 2 sec long), and repeats a few times before it stops. The best I can tell it happens only on the back wheel and does not happen all the time. Could this still be related to having a bad valve block? The actual pump seems to work fine.

Oh, I also get a chassis error that only says I can keep driving normally but should have it looked at. I'm assuming it's related to right side of the car not being stable.

-David
Where does the hissing sound come from? You said it is the whole right side (passenger side) that drops down, yes? Is the hissing coming from the rear drivers side? That is where you would hear it if the valve(s) for the passenger side were releasing the pressure.

What kind of environmental conditions is the car in? Hot and dry or cold and humid? Is the car normally parked on a hill or slope?
 

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Where does the hissing sound come from? You said it is the whole right side (passenger side) that drops down, yes? Is the hissing coming from the rear drivers side? That is where you would hear it if the valve(s) for the passenger side were releasing the pressure.

What kind of environmental conditions is the car in? Hot and dry or cold and humid? Is the car normally parked on a hill or slope?
This hissing sounds like when you are filling a balloon and then let the air out all at once. Not like a slow leak, but a all at once leak (if that makes sense).

It's happening on the passenger side rear wheel.
 

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This hissing sounds like when you are filling a balloon and then let the air out all at once. Not like a slow leak, but a all at once leak (if that makes sense).

It's happening on the passenger side rear wheel.
The hissing only comes from the passenger side rear wheel, or that's the corner that drops when you hear the sound? Did you say the entire passenger side of the car drops down over night?

Also, do have any way of reading error codes? If the ride height sensor in that corner of the car is bad or producing bad data the Vehicle Dynamics Platform (VDP) may think that air strut is extended too far and try to release pressure erroneously.
 

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The hissing only comes from the passenger side rear wheel, or that's the corner that drops when you hear the sound? Did you say the entire passenger side of the car drops down over night?

Also, do have any way of reading error codes? If the ride height sensor in that corner of the car is bad or producing bad data the Vehicle Dynamics Platform (VDP) may think that air strut is extended too far and try to release pressure erroneously.
Only the right side lowers (both front and rear). The hissing only comes from the rear, but I'll need to verify that.

I do have a way to read codes. I will check that out later today.

Let me add that the hiss is more like a burst of air.
 

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Last night I scanned for codes and got the following:

482974 VDP: Vehicle level - not adjustable
482963 VDP: Compressor relay - maximum switched-on period exceeded
483103 VDP: Vehicle extremely low - rear right
482953 VDP: Solenoid valve, pressure accumulator - maximum switched-on period exceeded
482936 VDP: Solenoid valve - rear right - maximum switched-on period exceeded

And like I mentioned in another post above, there are 4 to 5 bursts of air lasting ~2 seconds from the rear right wheel area after I turn off the car. I do not hear this from the front right wheel.

Does this still sound like it could be a valve block issue as suggested above?
 

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Does this still sound like it could be a valve block issue as suggested above?
It could be either the valve block or the air strut, the compressor is running for too long because the rear right is not holding air. Since you hear those bursts on the right side of the car, it's not the valve block as the compressor is on the left side. Can you get closer and feel for air around the air line connection?
 
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